Sweden has accused China of denying a request for Swedish prosecutors to board a Chinese ship that has been linked to the cutting of two undersea cables in the Baltic despite Beijing pledging “cooperation” with regional authorities.

The Yi Peng 3 left the waters it had been anchored in since last month on Saturday – despite an ongoing investigation.

The ship was tracked sailing over the two fibre-optic cables, one between Sweden and Lithuania, and the other linking Helsinki and Germany, at around the time that they were cut on 17 and 18 November in Swedish territorial waters close to the Swedish islands of Gotland and Öland.

For more than a month afterwards it was anchored in the Kattegat strait between Sweden and Denmark where it was being observed by multiple countries and was boarded by Swedish police and other authorities last week. The ship tracking site VesselFinder showed the Yi Peng 3 heading north out of the strait on Saturday and on Monday China confirmed the ship had left in order to “ensure the physical and mental wellbeing of the crew”.

The Swedish foreign minister, Maria Malmer Stenergard, said on Monday that China had not cooperated with Sweden’s request to allow Swedish prosecutors onboard.

“Swedish police have been onboard and attended as an observer in connection with the Chinese investigation,” she said. “The state’s accident commission took part in its role as the accident investigation authority. At the same time I can note that China has not listened to our request that the prosecutor should be able to conduct a preliminary investigation onboard.

“Our request that Swedish prosecutors, together with the police and others, be allowed to take certain investigative measures within the framework of the investigation on board remains. We have been clear with China on this.”

Stenergard said that although she expected talks to continue between Sweden and China “at different levels”, it was the prosecutor who had to decide what investigative measures should be taken.

“We have great respect for the preliminary investigation being conducted independently and we are still waiting for its findings,” she added. “I assume we will have continued talks with China about the matter, at different levels, to continue to make our argument and to work for the police and prosecutor to have the conditions to investigate what has happened.”

Earlier on Monday, China pledged to continue its cooperation with regional authorities over the ship.

“The shipowner company, after a comprehensive evaluation and consultation with relevant parties, decided to resume operations,” Mao Ning, a foreign ministry spokesperson told AFP. “China has notified all relevant countries in advance. China is willing to maintain communication and cooperation with the countries involved to advance the follow-up handling of the incident.”

Some European officials have said they suspect the cables were sabotaged in connection with Russia’s full-scale invasion of Ukraine. The Kremlin has rejected the accusations as “absurd” and “laughable”.

On Thursday, Swedish, German and Finnish authorities were invited to board the Yi Peng 3 along with a Danish representative as part of a Chinese-led investigation. But the Swedish prosecutor, which is leading a European investigation, was not permitted to board the vessel.

At the end of last month, the Swedish prime minister, Ulf Kristersson, said Swedish authorities had sent a formal request to China for cooperation over the suspected sabotage and was seeking “clarity” from China as to what had happened to the cables.

“Today I can tell you that we have additionally sent a formal request to work together with Swedish authorities to get clarity about what has happened,” he said then. “We expect China will choose to work together as we have requested.”

At the end of an unmarked path on a tiny island at the edge of Stockholm’s extensive Baltic Sea archipelago lies an inconspicuous little wooden cabin, painted a deep shade of red. Water gently laps the snow-dusted rocks, and the smell of pine fills the air.

The site offers few clues to the geopolitical drama that has gripped Scandinavia in recent months, driven by accusations of infrastructure sabotage. But in fact the cabin houses a key cog in Europe’s digital connectivity, and a point of vulnerability in a potential hybrid war: a datacentre that amplifies the signal from a 1,615-mile fibre-optic cable running from northern Sweden to Berlin.

Last month, two nearby fibre-optic cables were severed, prompting a continuing investigation by Swedish authorities. Western intelligence officials from multiple countries have said they are confident a Chinese ship caused the cuts after leaving the Russian port of Ust-Luga, though views differ on whether the cuts were accidental or potentially deliberate.

Since Russia’s invasion of Ukraine in 2022, Sweden has experienced a rise in hybrid warfare – attacks on an adversary using methods other than traditional military action – blamed on pro-Russia groups. With governments in northern Europe on high alert over hybrid Russian activity, the Guardian was given exclusive access to the Stockholm datacentre site.

Daniel Aldstam, the chief security officer at GlobalConnect, which transports 50% of the internet capacity of the Nordics and runs the centre, described the approach to its location and ordinary outward appearance as “security through obscurity”.

“Essentially you have two different approaches,” he said. “Either you put a lot of fences around it which make it obvious that there is something critical, or you do it like we have done it here and try to keep things a little more discreet. But of course we have the normal stuff in terms of alarms, CCTV, access control and all of that.” Inside, cages full of equipment emit blinking lights and different-coloured cables line the ceiling.

After a recent suspected sabotage incident, the Polish prime minister, Donald Tusk, proposed a “navy policing” initiative involving joint military patrols by countries around the Baltic.

Travelling from Stockholm by helicopter over the archipelago, formed of 30,000 islands, rocks and skerries, it is clear to see how challenging the coastline is to protect. But its vastness also suggests how the “security through obscurity” approach could be effective – at least up to a point. Maps that show where all the undersea cables are laid are publicly available.

“We have hundreds of thousands of kilometres of fibre. How do you physically protect it? You can’t,” said Aldstam. “What is important here is the redundancy [using multiple cables offering alternative routes if one is cut off]. You need to have more fibres.”

With infrastructure seen as being particularly vulnerable to hybrid warfare, there are signs of tweaks to the “obscurity” approach, reflecting the fraught times.

GlobalConnect is in the process of setting up a bigger and more modern-looking datacentre nearby, which although still unmarked and painted a similar shade of red, is more obviously a building doing an important function. Inside it has its own diesel-powered backup generator to ensure it could continue running if electricity was cut off.

The vulnerability to sabotage of undersea cables and other critical infrastructure – particularly in the relatively shallow and busy Baltic – has come into sharp focus since Russia’s full-scale invasion of Ukraine.

In September 2022, the Nord Stream pipeline, which carried natural gas from Russia to Germany, was blown up. Initially, many assumed Russia was to blame. However, in August this year, German media reported that German authorities had issued an arrest warrant for a Ukrainian man on suspicion of being part of a team that planted explosive devices on the pipeline. Both sides in the war in Ukraine have denied responsibility and blame each other for the attack.

Nato, which has established a dedicated centre for undersea security, has warned that the security of nearly 1 billion people across Europe and North America is at risk of hybrid warfare by the alliance’s adversaries, due to vulnerabilities in windfarm, pipeline and power cable infrastructure. Earlier this month, the Nato secretary general, Mark Rutte, urged Europeans to “shift to a wartime mindset”.

For all the warnings, undersea cables, which can lie on or be buried in the seabed, look surprisingly slight.

“We call it a super mega cable, but it doesn’t sound super mega or look super mega,” said Patrik Gylesjö, who is responsible for overseeing the whole of GlobalConnect’s Sweden to Berlin cable project, which was completed earlier this year. “The name refers to its capacity rather than the size.”

Inside the cable, which is little more than 2cm in diameter, is a small section formed of 96 hair-thin fibre pairs – enough to support 1bn simultaneous Netflix streams, he said. The rest is made up of steel armouring and a waterproofing substance.

It would take only an anchor from a relatively small ship to break the cable, said Gylesjö. “If you would like to break this cable or cut it, you would not need a super-big tool. It’s quite fragile.”

Making it stronger, he added, would make it heaver, more expensive and “more complicated to deploy”.

Accidental breaks in undersea cables are incredibly rare. “It’s very rare that damage happens in general,” said Gylesjö. “Very rare. During our time as an operator of sea cables [more than 20 years] I think it has happened two to three times maximum.”

At the end of an unmarked path on a tiny island at the edge of Stockholm’s extensive Baltic Sea archipelago lies an inconspicuous little wooden cabin, painted a deep shade of red. Water gently laps the snow-dusted rocks, and the smell of pine fills the air.

The site offers few clues to the geopolitical drama that has gripped Scandinavia in recent months, driven by accusations of infrastructure sabotage. But in fact the cabin houses a key cog in Europe’s digital connectivity, and a point of vulnerability in a potential hybrid war: a datacentre that amplifies the signal from a 1,615-mile fibre-optic cable running from northern Sweden to Berlin.

Last month, two nearby fibre-optic cables were severed, prompting a continuing investigation by Swedish authorities. Western intelligence officials from multiple countries have said they are confident a Chinese ship caused the cuts after leaving the Russian port of Ust-Luga, though views differ on whether the cuts were accidental or potentially deliberate.

Since Russia’s invasion of Ukraine in 2022, Sweden has experienced a rise in hybrid warfare – attacks on an adversary using methods other than traditional military action – blamed on pro-Russia groups. With governments in northern Europe on high alert over hybrid Russian activity, the Guardian was given exclusive access to the Stockholm datacentre site.

Daniel Aldstam, the chief security officer at GlobalConnect, which transports 50% of the internet capacity of the Nordics and runs the centre, described the approach to its location and ordinary outward appearance as “security through obscurity”.

“Essentially you have two different approaches,” he said. “Either you put a lot of fences around it which make it obvious that there is something critical, or you do it like we have done it here and try to keep things a little more discreet. But of course we have the normal stuff in terms of alarms, CCTV, access control and all of that.” Inside, cages full of equipment emit blinking lights and different-coloured cables line the ceiling.

After a recent suspected sabotage incident, the Polish prime minister, Donald Tusk, proposed a “navy policing” initiative involving joint military patrols by countries around the Baltic.

Travelling from Stockholm by helicopter over the archipelago, formed of 30,000 islands, rocks and skerries, it is clear to see how challenging the coastline is to protect. But its vastness also suggests how the “security through obscurity” approach could be effective – at least up to a point. Maps that show where all the undersea cables are laid are publicly available.

“We have hundreds of thousands of kilometres of fibre. How do you physically protect it? You can’t,” said Aldstam. “What is important here is the redundancy [using multiple cables offering alternative routes if one is cut off]. You need to have more fibres.”

With infrastructure seen as being particularly vulnerable to hybrid warfare, there are signs of tweaks to the “obscurity” approach, reflecting the fraught times.

GlobalConnect is in the process of setting up a bigger and more modern-looking datacentre nearby, which although still unmarked and painted a similar shade of red, is more obviously a building doing an important function. Inside it has its own diesel-powered backup generator to ensure it could continue running if electricity was cut off.

The vulnerability to sabotage of undersea cables and other critical infrastructure – particularly in the relatively shallow and busy Baltic – has come into sharp focus since Russia’s full-scale invasion of Ukraine.

In September 2022, the Nord Stream pipeline, which carried natural gas from Russia to Germany, was blown up. Initially, many assumed Russia was to blame. However, in August this year, German media reported that German authorities had issued an arrest warrant for a Ukrainian man on suspicion of being part of a team that planted explosive devices on the pipeline. Both sides in the war in Ukraine have denied responsibility and blame each other for the attack.

Nato, which has established a dedicated centre for undersea security, has warned that the security of nearly 1 billion people across Europe and North America is at risk of hybrid warfare by the alliance’s adversaries, due to vulnerabilities in windfarm, pipeline and power cable infrastructure. Earlier this month, the Nato secretary general, Mark Rutte, urged Europeans to “shift to a wartime mindset”.

For all the warnings, undersea cables, which can lie on or be buried in the seabed, look surprisingly slight.

“We call it a super mega cable, but it doesn’t sound super mega or look super mega,” said Patrik Gylesjö, who is responsible for overseeing the whole of GlobalConnect’s Sweden to Berlin cable project, which was completed earlier this year. “The name refers to its capacity rather than the size.”

Inside the cable, which is little more than 2cm in diameter, is a small section formed of 96 hair-thin fibre pairs – enough to support 1bn simultaneous Netflix streams, he said. The rest is made up of steel armouring and a waterproofing substance.

It would take only an anchor from a relatively small ship to break the cable, said Gylesjö. “If you would like to break this cable or cut it, you would not need a super-big tool. It’s quite fragile.”

Making it stronger, he added, would make it heaver, more expensive and “more complicated to deploy”.

Accidental breaks in undersea cables are incredibly rare. “It’s very rare that damage happens in general,” said Gylesjö. “Very rare. During our time as an operator of sea cables [more than 20 years] I think it has happened two to three times maximum.”

A source close to the Saudi government has told Agence France-Presse that Saudi authorities previously requested the extradition of the main suspect in Friday’s Christmas market attack in Germany, as multiple agencies admitted they had received warnings about him.

Echoing reporting from over the weekend, the source said Saudi Arabia had warned Germany “many times” about Taleb al-Abdulmohsen, a Saudi citizen with a history of spreading anti-Islamic propaganda on social media. He did not explain in what way he was considered potentially dangerous.

“There was [an extradition] request,” the source told AFP, without giving the reason for the request, adding that Riyadh had warned he “could be dangerous”.

Questions are mounting in Germany about whether Friday’s attack in Magdeburg, which killed five people, might have been preventable. Reports have emerged about lapses in security, questionable immigration decisions and attempts by police to confront the 50-year-old over threatening behaviour that were allegedly not followed through.

Abdulmohsen, a consultant psychiatrist, is being held in police custody on suspicion of murder, attempted murder and grievous bodily harm.

Four women and a nine-year-old boy were killed in the attack, when a black Mercedes SUV ploughed 400 metres into crowds of people at the Christmas market in the centre of Magdeburg, in eastern Germany. More than 230 people are now known to have been injured in the three-minute attack, 41 of whom remain in a critical condition. The injured figure was revised upwards on Monday, from a previous number of about 200.

Holger Münch, the head of Germany’s federal criminal police office, BKA, told German television Germany had received a warning from Saudi Arabia last year, but on investigation had found it too vague to act upon.

Police had attempted to approach Abdulmohsen for a so-called “threat analysis” discussion, but had apparently let the opportunity go after failing to find him at home.

His reputation for posting threatening messages online and in person is at the centre of the murder investigation. On Sunday, Christian Pegel, a state interior minister, said the suspect had referred to the 2013 Islamist terror attack on the Boston Marathon during a professional dispute at around that time.

In Magdeburg, where a sea of flowers and candles have been left at the site of the attack, the city’s 240,000 residents are trying to come to terms with what happened. City authorities criticised as “deeply disrespectful” the numerous attempts to politicise the attack.

The far-right, anti-immigrant Alternative für Deutschland, which is polling in second place in the run-up to a snap election in February, has invited its supporters to join a rally on the nearby cathedral square on Monday evening, despite the fact that Abdulmohsen had repeatedly expressed his support for the party and its affiliates on social media.

The AfD leader Alice Weidel is due to address attendees. The main focus will be on criticising the government’s immigration policies.

A counter-demonstration entitled ‘Don’t give hate a chance’ is due to take place at the same time, with participants being urged to form a human chain around the city.

On Saturday, far-right protesters from across Germany, dressed in black and disguising their faces, gathered in Magdeburg, shouting – in reference to immigrants – “throw them out”.

Germany’s interior minister, Nancy Faeser, has urged parties across the political divide to pull together and quickly pass laws on police reform and biometric surveillance that are at risk of being sidelined, delayed or scrapped altogether, following the collapse of the government last month.

In an interview with Spiegel, Faeser said: “It’s clear we must do everything in order to protect the people of Germany from such horrific acts of violence. To do this, our security authorities need all the necessary powers as well as more personnel.”

The opposition conservatives said Germany urgently needed a review of domestic security forces’ ability to access intelligence, in particular digital data, and were scathing about the fact that too often authorities are dependent on information from abroad to foil attacks on German soil.

“It cannot be the case any longer that we are satisfied with the fact that information about violent criminals and terrorists often only comes from foreign services,” Günter Krings, the CDU’s justice spokesperson, told German media.

He said it must be made easier for security services to apprehend dangerous people who are brought to their attention before they have the chance to carry out attacks.

Security at many Christmas markets around the country has been heightened following Friday’s attack, in which the attacker used a corridor meant for emergency vehicles to penetrate the market.

Police in the north-western city of Bremerhaven said they had arrested a 67-year-old man who had posted a TikTok video in which he had threatened to carry out knife attacks on people with dark skin in his local market on Christmas Day.

Donald Trump has moved to quash speculation about Elon Musk’s outsized influence in Republican politics, insisting at a conservative gathering that the tech billionaire would not usurp his authority as incoming president.

“No, he’s not going to be president, that I can tell you,” Trump told cheering supporters at the Turning Point USA conference in Phoenix on Sunday. “And I’m safe. You know why he can’t be? He wasn’t born in this country.”

The remarks came after a week in which Musk’s intervention helped derail a crucial government funding bill, prompting Democratic critics to mockingly refer to him as “President Musk.” It also led one Republican congressman on Sunday to compare Musk to a “prime minister” after praising his role in the funding fight.

“We have a president, we have a vice-president, we have a speaker. It feels like as if Elon Musk is our prime minister,” said Tony Gonzales, a Texas representative, on CBS News’ Face The Nation.

When pressed about Musk’s unelected status, Gonzales defended the billionaire as reflecting “the voice of the people”.

The Tesla chief executive and X owner allegedly posted more than 100 times against the original funding package, calling it “one of the worst bills ever written” and urging Republicans to shut down the government rather than support it. His social media barrage preceded similar opposition from Trump and helped tank support among congressional Republicans, forcing Mike Johnson, the House speaker, to craft a smaller alternative measure.

The episode highlighted Musk’s influence over Republican politics following his quarter-billion-dollar support for Trump’s campaign. While the president-elect has tapped Musk to co-lead a new non-governmental office focused on reducing government inefficiencies, the arrangement has raised fresh concerns from Democrats about potential conflicts of interest given Musk’s vast business empire.

During the funding bill debates last week, Rosa DeLaura, the Connecticut representative and top Democrat on the House appropriations committee, alleged in a letter to congressional leaders that Musk had worked to cut provisions that would have increased scrutiny of Chinese investments – suggesting his opposition was driven by concerns over protecting Tesla’s Shanghai manufacturing plant.

Chris Coons, a Democratic Delaware senator, warned the dynamic telegraphs further chaos, telling CNN’s State of the Union on Sunday: “We’re not just going to have President-elect Trump as a billionaire rage-tweeting at 4am. We’re going to have Elon Musk also injecting instability into how we tackle very complicated and important issues.”

Some political observers question how long the alliance can last, given Trump’s history of falling out with high-profile supporters who draw too much attention.

“When you initially begin in that role, you have enormous influence,” said Chris Christie, the former New Jersey governor, on ABC’s This Week on Sunday. “It will always decline. And that’s what happens. And you’ll see it. It will happen with Elon Musk, too.”

One other point of tension could be the war in Ukraine, one that Trump has promised to end swiftly which would come at the expense of Musk’s Starlink satellite internet service, which has become crucial to Ukraine’s effort.

Trump’s son, Donald Trump Jr, sought to downplay any friction, telling the conference in Phoenix last Thursday: “You see what the media is trying to do to break up the relationship that my father has with Elon. They’re trying to cause that schism to prevent these guys doing what they’re going to do best, and we cannot allow that.”

Greenland’s elected leader said the gigantic Arctic island is not for sale after Donald Trump once again raised the issue of “ownership and control” of the vast territory that has been part of Denmark for more than 600 years.

“Greenland is ours. We are not for sale and will never be for sale. We must not lose our long struggle for freedom,” Greenland’s prime minister, Múte Egede, said in a written comment.

The US president-elect on Sunday announced that he had picked Ken Howery, a former envoy to Sweden, as his ambassador to Copenhagen, and commented on the status of Greenland, a semi-autonomous part of Denmark.

“For purposes of National Security and Freedom throughout the World, the United States of America feels that the ownership and control of Greenland is an absolute necessity,” Trump wrote on Truth Social.

Trump, who takes office on 20 January, did not elaborate on the statement.

For many observers Trump’s comment triggered a sense of deja vu. During his first term Trump suggested in 2019 that the US should buy Greenland – which is home to the strategically important Pituffik US space base.

That idea was roundly rejected by Denmark as well as by the island’s own authorities before any formal discussions could take place. It also prompted widespread ridicule and became emblematic of the chaos that Trump brought to traditional global diplomacy – something now expected to happen again once Trump returns to the White House next month.

The Danish prime minister, Mette Frederiksen, in 2019 labelled Trump’s first offer as “absurd”, leading the then US president to describe her as “nasty” and to cancel a visit to the Danish capital of Copenhagen.

Separately on Sunday, Trump also threatened to reassert US control over the Panama Canal, accusing Panama of charging excessive rates to use the Central American passage and drawing a sharp rebuke from Panamanian president, José Raúl Mulino.

Reuters contributed reporting

Russian scientists have displayed the remarkably well-preserved remains of a baby mammoth found in the permafrost-covered region of Yakutia in Siberia.

The 50,000-year-old female mammoth has been nicknamed Yana after the river in whose basin it was discovered this summer. Experts say it is the best-preserved mammoth carcass in the world and is one of only seven whole remains ever found.

Studies will be carried out to work out her exact age at death, estimated at “one year old or a bit more”.

The carcass was shown at North-Eastern Federal University in the regional capital of Yakutsk, the institution said in a statement. “We were all surprised by the exceptional preservation of the mammoth,” said the university rector, Anatoly Nikolayev.

Maksim Cheprasov, a researcher, said it was a “unique discovery”.

The remains weigh 180kg (397lbs) and are 120cm (4ft) tall and 200cm long.

The carcass was dug up near the Batagaika research station where the remains of other prehistoric animals – including a horse, a bison and a lemming – have been found.

Before this discovery, only six mammoth carcasses had been found in the world – five in Russia and one in Canada, the university said.

Yakutia is a remote region bordering the Arctic Ocean. Its permafrost acts like a giant freezer that preserves the remains of prehistoric animals.

More than 1,000 North Korean soldiers have been killed or wounded since they were sent to fight alongside Russian troops in Ukraine, according to South Korean military officials.

In a statement released on Monday, the South’s joint chiefs of staff (JCS) said: “We assess that North Korean troops, who have recently engaged in combat with Ukrainian forces, have suffered around 1,100 casualties.”

The JCS did not say how many troops had been killed in action, but the claims underline the risks posed to the North’s untested armed forces, amid reports that the regime is poised to send further reinforcements to Ukraine.

Last week, South Korea’s spy agency claimed that at least 100 North Korean troops had died in the conflict since being sent into combat this month.

The high number of casualties could be attributed to the “unfamiliar battlefield environment, where North Korean forces are being used as expendable frontline assault units, and their lack of capability to counter drone attacks”, Lee Seong-kweun, a South Korean MP, told reporters after meeting intelligence officials.

Lee said “several North Korean casualties” had been attributed to Ukrainian missile and drone attacks, as well as training accidents, with the highest-ranking victim “at least at the level of a general”.

The JCS said it was “particularly interested in the possibility of additional deployments” to aid Russia’s war effort, adding that Pyongyang was “preparing for the rotation or additional deployment of soldiers”.

The statement said North Korea was also “producing and providing self-destructing drones” – thought to refer to attack drones – for use by Russia, along with rocket launchers and self-propelled artillery.

The deployment of North Korean soldiers marked a dramatic escalation in the war in Ukraine, as the Kremlin turned to its ally to boost its forces in the Kursk border region, where Ukrainian forces seized territory this year. It was also a demonstration of attempts by the Russian president, Vladimir Putin, to broaden the conflict through the direct involvement in fighting of a third country.

The once-unimaginable prospect of North Korean soldiers – members of the country’s 1.3 million-strong army – fighting in a European war became a reality months after Putin and Kim Jong-un signed a mutual defence pact at a summit in Pyongyang in June.

While details of the agreement have not been released, analysts believe the North Korean leader wants access to Russian rocket technology and other military know-how in exchange for providing its forces with ammunition, weapons and reinforcements.

Up to 12,000 North Korean troops have been deployed to help Russia in the war, according to US and South Korean officials. Pyongyang has also sent more than 10,000 containers of artillery rounds, anti-tank rockets, as well as mechanised howitzers and rocket launchers.

South Korea’s JCS said the North was also using the Ukraine theatre to modernise its warfare capabilities, adding: “This could lead to an increase in the North’s military threat toward us.”

In response, South Korea and Ukraine said last month they would deepen security cooperation, with the South’s now-impeached president, Yoon Suk Yeol, refusing to rule out providing Kyiv with weapons.

South Korea is a major arms exporter but has a longstanding policy of not sending weapons to countries that are engaged in conflict.

North Korea has not referred to its troop deployments or weapons shipments in official statements, but last week accused the US and its allies of “reckless provocation” for criticising its material support for Russia.

A foreign ministry spokesperson said the foreign ministers of 10 countries and the EU were “distorting and slandering” Pyongyang’s “normal cooperative” ties with Moscow, according to state media.

In a statement released by Washington, Ukraine’s allies urged North Korea “to cease immediately all assistance for Russia’s war of aggression against Ukraine, including by withdrawing its troops”.

More than 1,000 North Korean soldiers have been killed or wounded since they were sent to fight alongside Russian troops in Ukraine, according to South Korean military officials.

In a statement released on Monday, the South’s joint chiefs of staff (JCS) said: “We assess that North Korean troops, who have recently engaged in combat with Ukrainian forces, have suffered around 1,100 casualties.”

The JCS did not say how many troops had been killed in action, but the claims underline the risks posed to the North’s untested armed forces, amid reports that the regime is poised to send further reinforcements to Ukraine.

Last week, South Korea’s spy agency claimed that at least 100 North Korean troops had died in the conflict since being sent into combat this month.

The high number of casualties could be attributed to the “unfamiliar battlefield environment, where North Korean forces are being used as expendable frontline assault units, and their lack of capability to counter drone attacks”, Lee Seong-kweun, a South Korean MP, told reporters after meeting intelligence officials.

Lee said “several North Korean casualties” had been attributed to Ukrainian missile and drone attacks, as well as training accidents, with the highest-ranking victim “at least at the level of a general”.

The JCS said it was “particularly interested in the possibility of additional deployments” to aid Russia’s war effort, adding that Pyongyang was “preparing for the rotation or additional deployment of soldiers”.

The statement said North Korea was also “producing and providing self-destructing drones” – thought to refer to attack drones – for use by Russia, along with rocket launchers and self-propelled artillery.

The deployment of North Korean soldiers marked a dramatic escalation in the war in Ukraine, as the Kremlin turned to its ally to boost its forces in the Kursk border region, where Ukrainian forces seized territory this year. It was also a demonstration of attempts by the Russian president, Vladimir Putin, to broaden the conflict through the direct involvement in fighting of a third country.

The once-unimaginable prospect of North Korean soldiers – members of the country’s 1.3 million-strong army – fighting in a European war became a reality months after Putin and Kim Jong-un signed a mutual defence pact at a summit in Pyongyang in June.

While details of the agreement have not been released, analysts believe the North Korean leader wants access to Russian rocket technology and other military know-how in exchange for providing its forces with ammunition, weapons and reinforcements.

Up to 12,000 North Korean troops have been deployed to help Russia in the war, according to US and South Korean officials. Pyongyang has also sent more than 10,000 containers of artillery rounds, anti-tank rockets, as well as mechanised howitzers and rocket launchers.

South Korea’s JCS said the North was also using the Ukraine theatre to modernise its warfare capabilities, adding: “This could lead to an increase in the North’s military threat toward us.”

In response, South Korea and Ukraine said last month they would deepen security cooperation, with the South’s now-impeached president, Yoon Suk Yeol, refusing to rule out providing Kyiv with weapons.

South Korea is a major arms exporter but has a longstanding policy of not sending weapons to countries that are engaged in conflict.

North Korea has not referred to its troop deployments or weapons shipments in official statements, but last week accused the US and its allies of “reckless provocation” for criticising its material support for Russia.

A foreign ministry spokesperson said the foreign ministers of 10 countries and the EU were “distorting and slandering” Pyongyang’s “normal cooperative” ties with Moscow, according to state media.

In a statement released by Washington, Ukraine’s allies urged North Korea “to cease immediately all assistance for Russia’s war of aggression against Ukraine, including by withdrawing its troops”.

Joe Biden has commuted the sentences of 37 out of 40 federal death row inmates, changing their punishment to life imprisonment without parole.

The decision follows mounting pressure from campaigners who warned that the president-elect, Donald Trump, backs the death penalty and restarted federal executions during his first term after a 17-year hiatus.

“Make no mistake: I condemn these murderers, grieve for the victims of their despicable acts, and ache for all the families who have suffered unimaginable and irreparable loss,” Biden said in a statement released on Monday.

“But guided by my conscience and my experience as a public defender, chairman of the Senate Judiciary Committee, vice-president, and now President, I am more convinced than ever that we must stop the use of the death penalty at the federal level. In good conscience, I cannot stand back and let a new administration resume executions that I halted.”

It is the highest number of death sentences commuted by any president in the modern era. Among those spared is Len Davis, a former New Orleans police officer who masterminded a drug protection ring involving several other officers and arranged the murder of a woman, Kim Groves, who filed a brutality complaint against him.

Davis also helped send three men to prison for more than 28 years before they were found to have been wrongfully convicted of murder and freed in 2022.

During a brief interview Monday, Groves’s son Corey hailed Biden’s commutation of Davis’s death sentence, saying he always wanted the former officer to live as long as possible in prison. “I would like Len to wake up on his his 95th birthday and still be looking at concrete and barbed wire,” said Groves, who received a $1.5m settlement from the New Orleans city government in 2018 along with other family members over his mother’s murder. “I think that’s worse than any death sentence, so I don’t have any problem with what the president did.”

There is also a commutation for Norris Holder, who was sentenced to death for a two-man bank robbery during which a security guard died. Prosecutors said Holder may not have fired the fatal shot.

Another beneficiary is Daryl Lawrence, sentenced to death in the killing of Columbus, Ohio, police officer Bryan Hurst. Hurst’s former police partner Donnie Oliverio said in a statement: “Putting to death the person who killed my police partner and best friend would have brought me no peace. The president has done what is right here, and what is consistent with the faith he and I share.”

The clemency action applies to all federal death row inmates except three convicted of terrorism or hate-motivated mass murder: Dzhokhar Tsarnaev, convicted of carrying out the 2013 Boston marathon bombing attack; Dylann Roof, who shot dead nine Black church members in Charleston, South Carolina, in 2015; and Robert Bowers, who stormed a synagogue in the heart of Pittsburgh’s Jewish community and killed 11 worshippers in 2018.

The majority of the 40 men held on federal death row are people of color, and 38% are Black, Robin Maher, executive director of the Death Penalty Information Center, previously told the Guardian. Nearly one in four men were 21 or younger at the time of the crime.

Bryan Stevenson, the founder and executive director of the non-profit Equal Justice Initiative, said: “Today marks an important turning point in ending America’s tragic and error-prone use of the death penalty. By commuting almost all federal death sentences, President Biden has sent a strong message to Americans that the death penalty is not the answer to our country’s concerns about public safety.”

Martin Luther King III, the son of civil rights leader Martin Luther King Jr, added: “This is a historic day. By commuting these sentences, President Biden has done what no president before him was willing to do: take meaningful and lasting action not just to acknowledge the death penalty’s racist roots but also to remedy its persistent unfairness.”

Biden’s journey on the issue has been complicated. As a senator, he championed a 1994 crime bill that expanded the federal death penalty to cover 60 new offences. He boasted: “I am the guy who put these death penalties in this bill.” The legislation is now widely seen as having contributed to mass incarceration, particularly affecting Black men, and many of those currently on death row were sentenced under its provisions.

But during his 2020 presidential election campaign, Biden reversed his long-held support for capital punishment, pledging to eliminate it at the federal level. He cited concerns about wrongful convictions and racial disparities in the justice system.

The Biden administration duly imposed a moratorium on federal executions. Calls for the president to commute the federal death sentences mounted in recent weeks. He received letters from corrections officials, business leaders, Black pastors, Catholics, civil and human rights advocates, prosecutors, former judges, victim family members and others. Pope Francis publicly offered a prayer for those on federal death row, urging Biden to extend mercy to them.

The White House said Biden’s latest action would prevent the next administration from carrying out the execution sentences that would not be handed down under current policy and practice.

Under Trump, more people incarcerated in the federal system were put to death than under the previous 10 presidents combined. The Republican’s administration ended a pause of 17 years when it executed Daniel Lewis Lee, and followed that with six more executions between 16 July and 24 September 2020.

Two Democrats who sponsored bicameral legislation to ban the use of the death penalty at the federal level welcomed Monday’s announcement.

The Senate majority whip, Dick Durbin, chair of the Senate judiciary committee, said: “I have long advocated for the abolition of the federal death penalty and commend President Biden for this act of justice and mercy and for his leadership.”

Congresswoman Ayanna Pressley of Massachusetts praised Biden’s move as a “historic and groundbreaking act of compassion that will save lives, address the deep racial disparities in our criminal legal system, and send a powerful message about redemption, decency, and humanity”.

According to the White House, Biden has issued more commutations at this point in his presidency than any of his recent predecessors at the same point in their first terms. Earlier this month he announced clemency for about 1,500 Americans – the most ever in a single day – who have shown successful rehabilitation and a commitment to making communities safer.

Biden is also the first president to issue categorical pardons to individuals convicted of simple use and possession of marijuana and to former LGBTQ+ service members convicted of private conduct because of their sexual orientation.

Earlier this month the president sparked a political outcry by pardoning his son, Hunter, for federal felony gun and tax convictions that could have led to a prison sentence. Biden, who leaves office on 20 January, had repeatedly promised not to issue such a pardon.

Additional reporting by Oliver Laughland, Sam Levin and Ramon Antonio Vargas

Palestinian medics said Israeli airstrikes on Gaza killed at least 20 people overnight, including a strike on a tent encampment in al-Mawasi, an Israel-declared humanitarian zone, that left eight dead.

Two children were among the dead in the al-Mawasi strike, according to doctors at the Nasser hospital in Khan Younis, which received the bodies.

The hospital said it had recorded another six fatalities from a strike on individuals escorting an aid convoy, along with two additional deaths from an attack on a vehicle within al-Mawasi.

The al-Aqsa Martyrs hospital in the central city of Deir al-Balah said it had received three bodies after an airstrike on a school turned shelter in the built-up Nuseirat refugee camp.

The Israeli military says it strikes only militants, accusing them of hiding among civilians. It said late on Sunday that it had targeted Hamas fighters in the humanitarian zone. Hamas denies it operates among civilians.

The head of the Kamal Adwan hospital, one of the last functioning hospitals in northern Gaza, told Reuters Israel had ordered the evacuation of the facility.

Hussam Abu Safiya said that obeying the order was “next to impossible” because there were not enough ambulances to get patients out. Kamal Adwan hospital has been under repeated attack since Israel sent tanks into Beit Lahiya and nearby Beit Hanoun and Jabaliya in October.

“We currently have nearly 400 civilians inside the hospital, including babies in the neonatal unit, whose lives depend on oxygen and incubators,” Abu Safiya said. “We cannot evacuate these patients safely without assistance, equipment, and time. We are sending this message under heavy bombardment and direct targeting of the fuel tanks, which if hit will cause a large explosion and mass casualties of the civilians inside.’’

An IDF spokesperson told the Washington Post forces had not conveyed any evacuation warnings to the hospital this weekend.

Gaza’s health ministry has said the three main hospitals in northern Gaza – of which Kamal Adwan is one – are barely functioning.

Israels says the aim of the renewed assault on the north is to prevent Hamas fighters from regrouping there.

Tens of thousands of people are sheltering on Gaza’s exposed Mediterranean coastline, where they are facing harsh winter conditions with inadequate shelter, food and fuel. Temperatures are falling and a series of storms have destroyed makeshift tents.

Oxfam said only 12 out of the 34 trucks of food and water allowed to enter north Gaza over the last 10 weeks have managed to distribute aid to starving Palestinian civilians because of “deliberate delays and systematic obstructions” by the Israeli military.

Bushra Khalidi, Oxfam’s policy lead in the occupied Palestinian territory, told Al Jazeera: “After 14 months of relentless bombardment and starvation of the entire population, some people are acting out of desperation and there’s absolute chaos in Gaza right now.”

Khalidi added: “Some people are asking their kids not to play, because they will get dizzy since they’re not eating and drinking enough. Imagine asking your five-year-old not to play while already there’s all this death and destruction around.”

In the absence of electricity or gas, families residing in provisional camps across Gaza are enduring icy temperatures that could poses a grave risk to their lives.

Last month, Philippe Lazzarini, the head of the UN Relief and Works Agency for Palestine Refugees (Unrwa) said people in Gaza had been forced to burn plastic rubbish as a last resort to keep warm.

The recent developments come as Palestinian groups involved in the fighting said a ceasefire deal was “closer than ever”.

“The possibility of reaching an agreement is closer than ever, provided the enemy stops imposing new conditions,” Hamas, Islamic Jihad and the leftist Popular Front for the Liberation of Palestine said in a rare joint statement issued after talks in Cairo on Friday.

A Hamas leader told AFP on Saturday that talks had made “significant and important progress” in recent days.

On Monday, in an interview with the Israeli radio station 103fm, the far-right Israeli finance minister, Bezalel Smotrich, said the country needed a “big deal that does not include surrender to Hamas” in Gaza. “I believe that surrender deals that harm the great war achievements, harm us,” the leader of the ultranationalist Religious Zionist party said.

The war in Gaza began when Hamas-led militants attacked southern Israel on 7 October 2023, killing 1,200 people, mostly civilians, and abducting about 250 people. About 100 hostages are still inside Gaza, at least one-third of whom are believed to be dead.

Israel’s offensive has killed more than 45,200 Palestinians in Gaza, more than half of them women and children, according to the Gaza health ministry. Thousands more people are believed to be buried under the rubble and tens of thousands have been wounded.

The Israeli military says it has killed more than 17,000 militants, without providing evidence.

Agence France-Presse, Reuters and Associated Press contributed to this report

Honda, Nissan and Mitsubishi have confirmed they are in talks over a possible three-way merger as the Japanese companies struggle with falling sales and competition from Chinese brands.

The companies confirmed on Monday that Honda and Nissan had agreed to “start consideration towards a business integration through the establishment of a joint holding company”, and that Mitsubishi would also decide on joining by the end of January.

The merger would combine Japan’s second- and third-largest carmakers, and add the smaller Mitsubishi, in a defensive effort to join forces as the automotive industry goes through its biggest ever period of upheaval. It would create the world’s third-largest carmaker in terms of annual sales, behind only Japanese rival Toyota and Germany’s Volkswagen.

While Toyota has remained relatively financially resilient because of its early lead in hybrid vehicles, Japan’s other carmakers are struggling to come up with the money to invest in the switch away from polluting petrol and diesel to cleaner electric vehicles. Hybrids, which combine a petrol engine and a smaller battery, remain less expensive to produce for manufacturers.

At the same time, Chinese manufacturers such as BYD and SAIC have aggressively targeted electric cars as a way of grabbing a much bigger share of the global car market. China’s Foxconn, which makes iPhones under a contract with America’s Apple, had reportedly started early discussions about an approach for either Honda or Nissan, prompting accelerated merger talks.

Honda’s market value is 6.74tn yen (£34bn), compared with 1.67tn yen for Nissan and 717bn yen for Mitsubishi. Honda sold 3.8m cars in 2023, although it has been much more efficient than Nissan, which is worth a quarter of its rival despite selling 3m cars last year. Mitsubishi sold 700,000 cars in 2023.

Nissan has been in crisis mode for several years amid falling profits and the turmoil after the arrest of its former chief executive Carlos Ghosn in 2018.

Ghosn fled Japanese house arrest a year later, smuggled out of the country in a musical instrument box with the help of former special forces operatives.

Speaking from Lebanon, where he has lived since, Ghosn on Monday said the merger plans did “not make sense” and were unlikely to succeed, according to Reuters. He had led a semi-formal alliance between Nissan, Renault and Mitsubishi to try to achieve global scale, but he argued that Honda and Nissan were too similar to achieve much benefit.

“From an industrial point of view, there is duplication everywhere,” Ghosn said.

However, the three companies said the talks would respond to “the dramatic changes in the environment surrounding both companies and the automotive industry”.

Toshihiro Mibe, the Honda chief executive, said a change like this in the industry only came around every 100 years – suggesting that the switch to electric cars is as fundamental as the beginnings of the mass-market sale of cars.

He said that Nissan and Honda would “clarify the possibility of business integration by around the end of January in line with the consideration of Mitsubishi Motors”.

Makoto Uchida, the Nissan chief executive, said: “Honda and Nissan have begun considering a business integration, and will study the creation of significant synergies between the two companies in a wide range of fields.”

A leaked draft of a House ethics committee report on Matt Gaetz, the former Florida Republican congressman, found “substantial evidence” that he engaged in sex trafficking and paid for sex with a minor, among other serious violations of state law and congressional rules.

The draft investigation was obtained by CNN and concludes that Gaetz, Trump’s first pick for attorney general, made payments totalling tens of thousands of dollars to women for sex and drugs across at least 20 separate occasions. The draft report also states that in 2017 Gaetz paid a 17-year-old girl for sex, which would constitute statutory rape under Florida law.

“The committee determined there is substantial evidence that Representative Gaetz violated House Rules and other standards of conduct prohibiting prostitution, statutory rape, illicit drug use, impermissible gifts, special favors or privileges, and obstruction of Congress,” the GOP-led panel reportedly wrote in the investigation.

According to the final draft document reported by CNN, Gaetz used payment apps including Venmo and PayPal to transfer money directly to more than a dozen women during his time in Congress.

Investigators also highlighted a 2018 trip to the Bahamas where Gaetz allegedly “engaged in sexual activity” with multiple women. One woman told the committee that the trip itself served as “payment” for sexual services. The same witness reported that Gaetz took ecstasy during the Bahamas visit, which investigators determined violated House gift rules.

The Gaetz legal team, meanwhile, is fighting hard to keep the report from seeing the light of day, arguing in a new lawsuit on Monday morning: “If publicly released, would significantly damage plaintiff’s standing and reputation in the community.” It “would be immediate, severe and irreversible”. Gaetz has long maintained his innocence.

The report comes after a more than three-year investigation and represents a volte-face following an earlier committee vote not to issue the results of an inquiry it began in the spring of 2021, when Gaetz was the subject of an FBI investigation.

Its leak came nearly a month after Gaetz withdrew his nomination to be Trump’s attorney general amid a fierce backlash, partly fuelled by speculation over what the report might contain.

The House inquiry – triggered after the justice department launched a separate criminal investigation into Gaetz that was later dropped without charge – was instigated to look into a broad range of accusations.

These included allegations that he engaged in sexual misconduct and illicit drug use, shared inappropriate images on the House floor, misused state identification records, converted campaign funds for personal use and accepted gifts in breach of House rules.

Gaetz, who has denied all the allegations, in effect forestalled the report’s release by abruptly resigning from Congress last month after Trump nominated him as his attorney general in a decision that drew fierce bipartisan condemnation.

However, its contents became a subject of intense speculation as both Republican and Democratic senators voiced serious misgivings about Gaetz’s suitability to preside over America’s vast federal judicial and law enforcement structure.

Some critics accused Gaetz, a far-right representative from Florida, of resigning prematurely – long before the Senate had the chance to confirm or reject his nomination – with the purpose of preventing publication of the report, knowing its contents were likely to be damaging.

The ethics committee originally voted along party lines against releasing the document even as some senators demanded to see it in advance of Senate confirmation hearings that had been due to be held early next year. The Republican speaker, Mike Johnson – a close ally of Trump – vocally opposed releasing the report.

The change of heart is notable given that Gaetz later said he would not attempt to return to Congress after withdrawing his nomination.

Gaetz’s angrily condemned the committee’s revised decision – first reported by CNN – in a vitriolic social media post on Wednesday, pointing out that he was never criminally charged.

“The Biden/Garland DOJ spent years reviewing allegations that I committed various crimes,” he wrote.

“I was charged with nothing: FULLY EXONERATED. Not even a campaign finance violation. And the people investigating me hated me.

“Then, the very ‘witnesses’ DOJ deemed not-credible were assembled by House Ethics to repeat their claims absent any cross-examination or challenge from me or my attorneys. I’ve had no chance to ever confront any accusers. I’ve never been charged. I’ve never been sued.

“Instead, House Ethics will reportedly post a report online that I have no opportunity to debate or rebut as a former member of the body.”

He described his 30s – his age range when the alleged misconduct occurred – as a time of “working very hard – and playing hard too”.

“It’s embarrassing, though not criminal, that I probably partied, womanized, drank and smoked more than I should have earlier in life.”

But in a pointed jab at the House’s current ructions over a continuing resolution (CR) bill on public spending aimed at keeping the government open, he concluded: “At least I didn’t vote for CR’s that fuck over the country!”

Denzel Washington has become a minister after being baptised shortly before his 70th birthday, in a ceremony at a church in New York.

The Oscar-winning actor, now appearing in Gladiator II, was baptised on Saturday at the Kelly Temple Church of God in Christ in Harlem, New York City, affiliated to the Pentecostal Church of God in Christ denomination. The service was livestreamed on Facebook, showing Washington, wearing a white robe, being immersed in the church’s ritual pool and being presented with a certificate of baptism.

Mentioning he was about to turn 70 on 28 December, Washington told the congregation: “It took a while, but I’m here.” He also spoke about an incident when he was 20 in which he encountered a woman called Ruth Green in his mother’s beauty parlour, who told him: “Boy, you are going to travel the world and preach to millions of people.”

Later in the ceremony, Washington was given a minister’s licence by the church, which would enable Washington to officiate at minor religious services, such as weddings, and allow him to be ordained in the future.

In an interview with Esquire in November, Washington described his moment of religious awakening in the early 1980s in a church in Los Angeles. “It felt like I was getting lifted up. It felt like my back was arched, and I had my eyes closed. Not that I was going up in the air, but – I can’t exactly describe it. And I was blabbering, and kept blabbering, because I was filled with the Holy Spirit.”

In the same interview Washington also alluded to the difficulties he faced being open about his faith in the film industry. “You can’t talk like that and win Oscars. You can’t talk like that and party. You can’t say that in this town … It’s not talked about in this town. It’s not talked about … It’s not fashionable. It’s not sexy. But that doesn’t mean people in Hollywood don’t believe.”