Israeli security forces on Tuesday embarked on a military operation in Jenin, a Palestinian city in the Israeli-occupied West Bank, as Israel turned its focus to an area seen as a hotbed of militancy just days after a temporary cease-fire took hold in Gaza.

Prime Minister Benjamin Netanyahu of Israel said in a statement that the operation, the latest in a string of West Bank raids over the past year, was aimed at “eradicating terrorism” and would be “extensive and significant.” The Palestinian Authority’s health ministry reported that eight people had been killed and at least 35 injured during the first hours of the operation.

For Mr. Netanyahu, the operation in the West Bank could serve as a distraction from Gaza, where Hamas gunmen paraded through the streets even before the cease-fire started on Sunday, a show of force signaling that it had survived the 15-month war despite Mr. Netanyahu’s vows to destroy it.

But with its strength severely diminished in Gaza, Hamas has intensified its efforts to arm militants in the West Bank to open another front against Israel, analysts said, making an Israeli offensive there almost inevitable.

The Jenin operation comes amid sharply rising tensions in the West Bank, as the militants have grown in power and settler violence against Palestinian civilians has soared.

On Monday, President Trump rescinded sanctions imposed by the Biden administration last year on dozens of far-right Israeli individuals and settler groups accused of violence against Palestinians and the seizure or destruction of Palestinian property.

The move came shortly after Mr. Trump took office, even as Jewish extremists raided several Palestinian villages, setting fire to vehicles and properties, according to Palestinian officials and the Israeli military.

The Palestinian Authority, which exercises limited control over parts of the West Bank and is a rival of Hamas, has been carrying out its own operation against armed militants in Jenin in recent weeks after largely leaving security in the area to Israel. Deadly Israeli raids and drone strikes in the northern West Bank over the past year have chewed up streets and left many Palestinian civilians in fear.

Residents and witnesses in Jenin said on Tuesday that a local private hospital, Al-Amal, was surrounded by Israeli forces and had come under fire.

“It’s as if they came to us straight from Gaza with large vehicles, aggressive gunfire and drones,” said Kamila Mahmoud, 22, a resident of Jenin, in a telephone interview.

Residents said that Palestinian Authority security officers and medics were among the injured. Brig. Gen. Anwar Rajab, the spokesman for the Authority’s security forces, said one Palestinian officer was killed.

The Israeli military did not immediately respond to questions about the accounts.

Presaging the raid in Jenin, Lt. Gen. Herzi Halevi, Israel’s military chief, said in a statement on Monday, the day after the cease-fire in Gaza came into effect, that Israel “must be ready for significant counterterrorism operations” in the West Bank in the coming days “to pre-empt and apprehend the terrorists before they reach our civilians.” Mr. Halevi announced his resignation on Tuesday, citing in part the military’s failure to protect Israel from the Oct. 7, 2023, Hamas-led assault that prompted the Gaza war.

Nearly half a million settlers and roughly 2.7 million Palestinians live in the West Bank. The Palestinians, and much of the world, have long envisioned the territory as part of a future independent Palestinian state, alongside Israel, and consider the Jewish settlements to be illegal.

Though Mr. Trump has sent mixed signals, his administration is expected to be staunchly pro-Israel. Some settler leaders have nurtured close ties over the years with Trump associates like Mike Huckabee, Mr. Trump’s pick as the next ambassador.

Hard-line members of Israel’s right-wing government had been requesting the removal of the Biden administration sanctions, one of a long list of executive orders that Mr. Trump signed immediately after his inauguration. Palestinian officials strongly criticized the move, saying it was likely to encourage further violence.

The cancellation coincided with a second consecutive night of violence in the West Bank as extremist settlers protested the cease-fire. Yisrael Ganz, the leader of an umbrella council representing all the settlements, welcomed Mr. Trump’s decision but said he condemned all violence, even if it was perpetrated by a “handful” of settlers.

Far-right members of Mr. Netanyahu’s government oppose the cease-fire, the first phase of which calls for a six-week truce and the incremental exchange of 33 hostages held in Gaza for hundreds of Palestinian prisoners.

Pressure from Mr. Trump and his envoy, Steve Witkoff, was instrumental in helping seal the deal between Israel and Hamas, as were Biden administration officials and other mediators. Mr. Trump had warned that there would be “all hell to pay” if Israeli hostages were not released by his inauguration.

But asked on Monday if he thought the cease-fire in Gaza would hold, Mr. Trump said that he was “not confident” and signaled a lack of interest in the conflict. “That’s not our war,” he said. “It’s their war.”

“But I think they’re very weakened on the other side,” he added, apparently referring to Hamas.

Hamas has become increasingly isolated with its allies decimated in Lebanon, toppled in Syria and weakened in Iran. Seeking to ignite another front against Israel, Hamas issued a statement on Tuesday calling on the Palestinian masses to mobilize and confront the Israeli forces in the West Bank.

“That’s the only front where they see a potential,” said Ehud Yaari, an Israel-based fellow of the Washington Institute for Near East Policy.

Noting that Israel had already raided Jenin more than a dozen times over the past year, Mr. Yaari said that Israel had no choice but to mount a large-scale operation there because the Palestinian Authority’s efforts appeared to be failing. Hamas was supplying the West Bank gunmen with funds and more sophisticated weapons, and attacks against Israel were intensifying, he noted.

General Rajab, the spokesman for the Palestinian Authority’s security forces, said the Israeli raids were “aimed at undermining the security campaign being conducted by the Palestinian Authority” and “intentionally sabotaging Palestinian efforts to enforce law and order” by creating chaos.

Settler extremists have also been trying to destabilize the West Bank and said they would try to block Palestinian prisoners released under the terms of the Gaza cease-fire deal from returning to their homes. Israeli security chiefs have labeled the settler attacks on Palestinians as Jewish terrorism.

One of the Palestinian towns that came under settler attack on Monday was Al-Funduq, in the northern West Bank, where Palestinian gunmen who are believed to have come from another town shot at a civilian bus and cars, killing three Israelis earlier this month.

Louay Tayem, the mayor of Al-Funduq, said that dozens of Israeli settlers began raiding the village, as well as neighboring Jinsafut, at around 9:15 p.m. on Monday and that the assault continued for roughly three hours before the settlers were finally dispersed by Israeli security forces. They smashed car windows, torched a plant nursery and two bulldozers, and attempted to set a house on fire, he said in a phone interview.

Two Israeli men were shot and seriously wounded during one of the assaults on Monday, according to Israel’s emergency services, apparently by Israeli security forces who came under attack. The Israeli authorities said they were investigating.

Aaron Boxerman and Myra Noveck contributed reporting from Jerusalem and Rawan Sheikh Ahmad from Haifa, Israel.

As panic sank in, two men strung ladders together with rope and placed them over the steel border wall that separated Tijuana from Southern California.

“Hurry up, hurry keep moving!” shouted the smugglers at the bottom of the ladder. A young girl from Zimbabwe stood on top and looked down with wide eyes, hesitating before taking her next step.

On Monday, people waiting to enter the United States learned that President Trump had canceled all asylum appointments moments after taking office and planned to sign several executive orders sealing the border.

Yet at least one group still made a desperate and perilous last-ditch effort to cross into the United States.

One by one, they ascended the wobbling structure, then slid down the other side. Those who made it over helped catch the women and children. But one woman fell to the ground on her way down and lay wailing in pain, grabbing her leg.

“We do this out of need, not because we want to, and that is it,” said Carlos Porras, 39, from Peru, speaking through the wall slats. He also hurt his ankle while jumping and was limping.

Moments later, the group was approached by U.S. Border Patrol officers and taken away.

The scene revealed the desperation of migrants who on Monday learned that the border was now effectively closed. All were left to process the emotions, from bewilderment to despair.

“I feel rage, I feel sadness, I feel everything,” said Katherine Romero, 36, a Venezuelan who had waited a year in Mexico City for her Monday asylum appointment, working different jobs to save up for the plane ticket to Tijuana. “I just can’t believe it.”

In a series of orders he signed on Monday evening, Mr. Trump moved to close the nation’s borders to migrants, part of a policy barrage that included broadly blocking asylum seekers and a national emergency declaration to deploy the military to the border.

His administration shut down the CBP One app just minutes after Mr. Trump took the presidential oath on Monday. The app was used by the Biden administration to allow migrants to schedule appointments to gain entry into the United States but had been a target of Republicans.

The program allowed 1,450 people a day to schedule a time to present themselves at a port of entry and request asylum. More than 900,000 entered the country using the app from its launch to the end of 2024.

In a migrant encampment in Mexico City on Monday, Cristian Morillo Romero, a Venezuelan who arrived in Mexico over a year ago, learned that Mr. Trump had ended the CBP One program — but he didn’t know what that meant for his Jan. 26 appointment in Calexico, Calif.

Then he opened his email. There was a message in English with the subject line “CBP One Appointment Canceled” that explained that existing appointments “are no longer valid.”

“I want to cry,” said Mr. Morillo Romero, 37. When it finally hit him later in the day, he did.

In Ciudad Juárez, across the border from El Paso, only one group of 100 people was allowed to cross into the United States for their early morning appointments. Then, just before 11 a.m., Mexican border officials said they received a notification from their American counterparts: No more appointments were being accepted.

“I’m in shock,” said John Flores Bonalte, 36, a Venezuelan who never got to his 1 p.m. appointment. “It’s unfair. We were waiting to cross legally for a long time. It’s been seven months waiting in Mexico for this appointment.”

José Antonio Zuchite, 40, said he left Honduras in September and waited five months in Mexico City before coming to Ciudad Juárez over the weekend “with a lot of hope.” His appointment on Monday was then canceled.

“I don’t have a place to stay,” he said, as his voice cracked. “I don’t have family or acquaintances here. I’m on the street.”

On social media, migrants shared images and videos of themselves, crying or with their heads in their hands, along with captions detailing how long they had been waiting for appointments. Many said they had been biding their time in Mexico. Some said they had waited more than a year.

Many of the videos featured the same clip from a song that had also served in recent years as a sort of anthem for people who finally made it to the United States.

Now many were scrambling. In Tijuana, some people considered staying while praying for some sort of miracle. Others said they were thinking about going to places like Mexico City, where there were more job opportunities. Some said returning to their native countries was out of the question because they were escaping violence or threats.

“Going back to Haiti means going back to death,” said Rose Joseph, 28, who left the country’s violence-torn capital more than two years ago.

In her Monday news conference, President Claudia Sheinbaum of Mexico strongly urged Mr. Trump’s team to replace the CBP One app with another mechanism so that people could again apply for asylum in an orderly way.

“We want something similar to be established, because it has had results,” she said.

The program was a key part of the Biden administration’s effort to gain control over migration through the southern border. U.S. officials at the time believed that by offering migrants an organized way to enter legally through an app, they could discourage unauthorized crossings.

Coupled with Mexico’s hardened restrictions, unlawful crossings dropped markedly in 2024 and officials and analysts say the app was a significant reason.

“That was a massive change,” said Ariel Ruiz Soto, a senior policy analyst at the Migration Policy Institute in Washington. “It provided more stability and an opportunity to have better control on both sides of the U.S.-Mexico border, because it made the path of migrants more predictable.”

Critics, though, viewed the program as a way to allow those who otherwise had no legal pathway into the United States to come and remain for years as their immigration cases languished in the courts.

“They made an application to facilitate illegal immigration,” Vice President JD Vance said in a post on X last week. “It boggles the mind.”

Without a replacement program, migrants stranded in Mexico likely face three scenarios: try to cross illegally into the United States, return to their home countries or apply for asylum in Mexico.

“Maybe it’s not what many migrants would like, but it’s an alternative,” Mr. Ruiz Soto said. Still, he added, that would not be of much help for Mexicans seeking to flee their own country. “For them, I don’t see many options.”

Francisco González, a pastor who oversees a network of migrant shelters, including one in Ciudad Juárez, said he expected migrants to stay longer at shelters as they planned their next steps. He worried, he said, that people might now assume more risk by hiring smugglers or members of organized crime to cross the border illegally.

“They’re going to keep trying,” he said.

Aline Corpus contributed reporting from Tijuana and Emiliano Rodríguez Mega and Annie Correal from Mexico City.

The teenager had become increasingly withdrawn, even from his family. He rarely left his home, a red brick house on a quiet cul-de-sac in the village of Banks, near the west coast of England.

Alone with his thoughts, he scrolled endlessly through online images and descriptions of war, torture and death, feeding an obsession with genocide and killing.

And then, on a bright morning last summer, Axel Rudakubana took a taxi to a children’s dance class in Southport, England. Knife in hand, he rampaged through a crowded room where girls on their summer break had gathered to dance to Taylor Swift and make friendship bracelets. He murdered three of them, and he wounded eight other children and two adults.

In the months since the July 29 attack, the police and prosecutors have worked to retrace the steps leading up to the killing spree, which horrified Britain. They interviewed witnesses, examined hours of CCTV and reviewed thousands of documents, downloads and messages from Mr. Rudakubana’s devices.

On Monday, after Mr. Rudakubana, now 18, pleaded guilty to murder and other charges related to the Southport attack, restrictions on reporting about his case were lifted.

The picture that has emerged, while still limited, is of a deeply troubled individual whose fascination with violence was brought to the authorities’ attention when he was just 13, and who had been known to a number of state agencies for years.

“It is clear that this was a young man with a sickening and sustained interest in death and violence,” Ursula Doyle, the deputy chief crown prosecutor for the Mersey-Cheshire region, said outside the courtroom where Mr. Rudakubana entered his guilty plea. “He has shown no sign of remorse.”

As the details of Mr. Rudakubana’s interactions with local agencies came into focus on Monday, it became clear that the authorities may have missed opportunities to stop the violence before it began. He had been referred three times to Prevent, a counterterrorism program, when he was 13 and 14 because of his fixation on violence, the government confirmed on Monday. He had also come into contact with the police, the courts, social services and mental health services in the years before the attack.

Yvette Cooper, Britain’s home secretary, said in a statement that the agencies had “failed to identify the terrible risk and danger to others that he posed.” She announced a public inquiry to determine “the truth about what happened and what needs to change.”

Ms. Cooper said the information about Mr. Rudakubana’s previous referrals to the authorities could not have been made public before his conviction. Strict rules govern the release of information during active court proceedings in Britain in order to guarantee the right to a fair trial.

The police found ricin, a lethal toxin, in Mr. Rudakubana’s house, as well as a PDF file titled “Military Studies in the Jihad Against the Tyrants: The Al Qaeda Training Manual.” But his online history showed a wide interest in conflict, terrorism and genocide, and there was no evidence that he subscribed to a single political or religious ideology, according to the Merseyside Police.

Instead, they said, he seemed to have been driven simply by a desire to commit violence.

“Although we will never know why he did it, what we can say is that he was a man with an unhealthy obsession with extreme violence,” Serena Kennedy, the chief constable of the Merseyside Police, said in a statement.

“We know that he had researched numerous documents online which show that obsession. What we can say is that, from all those documents, no one ideology was uncovered, and that is why this was not treated as terrorism.”

‘Unwilling to leave the house’

Mr. Rudakubana was born in Cardiff, Wales, in 2006 to parents who were originally from Rwanda. They moved to the Southport area in 2013; at the time of the attack, the family was living in Banks, a small village nearby. His father, Alphonse Rudakubana, had moved to Britain in 1996 in the wake of Rwanda’s genocide, according to a 2015 profile in the Southport Visiter, a local paper.

In interviews soon after Mr. Rudakubana’s arrest last year, residents of Banks, which is home to about 4,400 people, said he had mingled little with the community.

During a pretrial hearing in Liverpool in August, a prosecutor told the court that Mr. Rudakubana had been diagnosed with autism spectrum disorder, adding that he had been “unwilling to leave the house and communicate with family for a period of time.”

For a while, Mr. Rudakubana seemed to have an interest in acting and was represented by a talent agency, even playing Doctor Who in a BBC advertisement in 2018 when he was 11 years old. But by the end of the following year, he was on the authorities’ radar.

In October 2019, he brought a knife into his school, according to a statement on Monday from the Lancashire Child Safeguarding Partnership, which oversees child protection in the area.

He was subsequently expelled from the school, which the BBC identified as Range High School in Formby. An administrator there declined a request to comment. Owais Patel, 18, a resident of Banks, told The New York Times soon after the attack that it was widely known among young people in the village that Mr. Rudakubana had been expelled for bringing a weapon to school.

A number of agencies became involved after that incident, according to the safeguarding partnership, which said Mr. Rudakubana had experienced “increasing anxiety and social isolation” and had developed “some challenging behaviors.”

In December 2019, Mr. Rudakubana returned to the school with a hockey stick and physically assaulted a student, the agency said.

At least three times between December 2019 and April 2021, education providers referred Mr. Rudakubana to Prevent, the counterterrorism program, the head of counterterrorism policing said on Monday. Created in the wake of the 9/11 attacks, Prevent tries to intervene in the lives of people suspected of being vulnerable to radicalization, with the hope of diverting them from possible terrorism.

But each time, it was determined that he did not meet the threshold for intervention, Prime Minister Keir Starmer said on Tuesday. That judgment “was clearly wrong” and failed the victims’ families, he said. He announced a review into whether the law needed to change to reflect the new threat posed by extremists like Mr. Rudakubana who do not subscribe to any particular ideology.

After his expulsion, Mr. Rudakubana was enrolled at the Acorns School in Lancashire, which caters to children with special needs, and at Presfield High School and Specialist College. But he struggled to integrate, the safeguarding agency said, a situation that worsened after the pandemic began in 2020 and schools closed. Despite professionals’ efforts to engage with him, he “continued to face challenges related to his emotional and behavioral well-being, social interactions and education,” the agency said, and his attendance was limited.

‘Savagery and senselessness’

On July 22, Mr. Rudakubana booked a taxi to take him to Range High School, according to a local police official. But his father ran outside and pleaded with the driver not to take him, and eventually Mr. Rudakubana returned to the house. CCTV footage showed him wearing the same hooded sweatshirt and mask that he would wear a week later, during the Southport attack. No more information was provided on the incident.

On that morning of the attack, two teachers set up a room at Hart Space, a yoga and community studio in Southport. They laid out a station for bracelet making and an area for yoga, and they lined up a playlist of Taylor Swift songs, ready for the 26 youngsters who arrived around 10 a.m. The class had been advertised on an Instagram account and had quickly sold out.

As the class neared its end, just before noon, Mr. Rudakubana arrived in a taxi and walked into the building, where he stabbed to death Bebe King, 6, Elsie Dot Stancombe, 7, and Alice da Silva Aguiar, 9. Eight other children were wounded, along with Leanne Lucas, the organizer of the event, who tried to shield the children, and John Hayes, a businessman who worked nearby and who tried to tackle Mr. Rudakubana.

After the attack, detailed examinations of Mr. Rudakubana’s digital devices revealed images related to wars and conflict around the world, including victims of torture and graphic descriptions of killings.

On Thursday, he will appear in Liverpool Crown Court for his sentencing. The judge presiding over his case has indicated that he will face life in prison.

Speaking outside the courtroom on Monday, Ms. Doyle, the deputy prosecutor, said the attack had left “an enduring mark on our community and the nation for its savagery and senselessness.”

But she expressed relief that Mr. Rudakubana’s guilty plea, which had not been expected, meant the families of the victims would be spared the pain of reliving their ordeal at a trial.

“Most of all,” she said, “we think of Elsie, Bebe, and Alice — the three beautiful young girls whose lives were cut short — and wish strength and courage to the families who loved and cherished them.”

Lynsey Chutel reported from Banks and Southport, England, Stephen Castle from London and Jacob Judah from Liverpool, England.

A fire blazed through a 12-story hotel at a ski resort in Turkey on Tuesday, killing at least 76 people and injuring 51 others, the authorities said, turning an idyllic vacation spot into a smoke-filled nightmare.

The disaster struck during Turkey’s winter holiday, when children are out of school and many families go on vacation, including to ski resorts. It was not clear how many children were among the dead, but a number were reported by acquaintances.

The cause of the fire was unclear.

Justice Minister Yilmaz Tunc said on social media that six prosecutors had been assigned to investigate the blaze. Nine people, including the hotel’s owner, had been detained.

The fire broke out before dawn in the Grand Kartal Hotel in Kartalkaya, 180 miles east of Istanbul, sending large flames from the windows and thick smoke billowing from the roof.

About 230 guests were believed to be in the hotel at the time, in addition to a number of employees. Some survivors told the Turkish news media of terrifying escapes, exacerbated by a lack of fire alarms or clear fire escapes.

“The smoke was so intense that we could hardly breathe,” Eylem Senturk, who was vacationing at the hotel with her family, told the state-run Anadolu news agency.

She and her daughter raced downstairs to an exit, but the smoke was too intense for her husband, she said, so he jumped from a window onto a lower rooftop and then onto a car to reach the ground.

Ms. Senturk said she had not heard a fire alarm, but realized that the building was burning when she heard people shouting in the hallway and opened the door to see smoke. She did not see any fire escapes, she said.

“If there had been a fire alarm, we could have been faster,” she said. “The lack of a fire alarm and fire escape trapped people.”

Another survivor, Muzaffer Cig, also told Anadolu that there was no fire escape. “As there was no fire escape, we ran down the staircase,” he said.

Speaking to reporters at the scene, Tourism Minister Mehmet Nuri Ersoy said that the hotel had been inspected in 2021 and 2024 and was found to have the necessary fire precautions. He also said the building had two fire escapes.

But no external escapes are visible in aerial footage of the building broadcast on Turkish television after the fire.

Fifty-two of the victims have been identified, and 14 were sent to forensic medicine unit for further DNA testing, officials said. The bodies of 45 people were turned over to their families.

Turkey declared a day of national mourning.

The dozens of deaths in a building surrounded by snow-capped peaks where families had gone expecting good times prompted calls for accountability, but such calls after past disasters have not gone far.

After powerful earthquakes killed more than 50,000 people in southern Turkey in early 2023, survivors and engineers accused contractors and government inspectors of failing to ensure compliance with building codes, increasing the death toll. Nearly two years later, however, few people have been held accountable.

The fire on Tuesday started at around 3:30 a.m., when most hotel occupants were asleep, according to news reports. In an effort to evacuate, some strung bedsheets together to make a rope that they used to descend to a lower floor, video footage showed.

Dozens of rescuers and fire trucks rushed to the site from surrounding towns.

“When I left my room, I saw the flames at the fourth floor, the floor of the restaurant,” Necmi Kepcetutan, a ski instructor who also worked at the hotel, told the NTV network. “Then it started to swarm the hotel. We helped around a dozen or more people to evacuate, since we know the hotel very well.”

“People were screaming to be rescued,” he added.

Two people — a guest and a hotel employee — died after jumping from the building, the area’s governor, Abdulaziz Aydin, told Anadolu.

The fire took place on the same day that an explosion injured four people at another Turkish ski resort, in the central province of Sivas, its governor’s office said in a statement.

The reason for the explosion was unclear. Two skiers and a trainer were lightly injured, while another trainer had second-degree burns on the hands and face, the statement said.

As Donald J. Trump took the oath of office in Washington on Monday, the crowd at a jam-packed party held by Ukrainian business groups in Davos, Switzerland, intently watched the ceremony on huge screens.

The event, on the sidelines of the World Economic Forum’s annual conference, seemed to be a display of enthusiasm for the returned American president. Speakers praised Mr. Trump and predicted that he would be a valuable partner for Ukraine in its war against Russia, despite his criticism of U.S. spending on the military effort. Waiters served mini cheeseburgers on red-and-blue buns (“American food,” attendees whispered). A few people applauded at the end.

Yet the apparent optimism was a thin veneer over deep uncertainty.

“We expect President Trump to surprise us, but we do not know what the surprise will be,” Andy Hunder, president of the American Chamber of Commerce in Ukraine, said at the party.

Mr. Trump’s return to the White House has plunged Europe’s business leaders and policymakers into a precarious era, and officials have been bracing for it behind the scenes. The European Commission — the European Union’s executive arm — formed a never-officially-announced group, sometimes colloquially referred to as a “Trump task force,” which spent much of 2024 working on possible responses to changes to American trade and foreign policy.

There is almost no aspect of European policy that Mr. Trump does not seem poised to upend. He is threatening to impose sweeping tariffs and is pressing for much heftier European spending on defense. Two of his first acts as president were to withdraw from the Paris climate agreements and the World Health Organization.

How he will adjust America’s stance toward Ukraine is one of the biggest questions: During his campaign, he pledged to end the war on his first day in office, though that timeline has crept back and he has not said how.

Yet it is difficult for companies and government officials to know what is bluster, or bargaining chip, and what is reality. And they have learned from the first Trump administration that criticizing the American president too overtly might accomplish little and could draw attention and even retribution.

So companies and governments alike are treading carefully to curry favor with, or at least avoid angering, the mercurial president of the world’s most powerful nation.

The European Commission is a case in point. Staff members on the task force spent 2024 researching possible detailed responses to the new American presidency. But in public, top officials have expressed only a willingness to negotiate in response to potential tariffs and other threats, while vaguely warning that they would retaliate to protect the bloc’s own interests if necessary.

Ursula von der Leyen, the commission’s president, suggested in the days after Mr. Trump’s election that Europe could buy more American liquid natural gas. That is something Mr. Trump has said Europe must do to avoid tariffs.

“The one thing they can do quickly is buy our oil and gas,” Mr. Trump reiterated to reporters in the White House after his inauguration on Monday. “We will straighten that out with tariffs, or they have to buy our oil and gas.”

But Ms. Von der Leyen has often spoken only in generalities about how Europe might respond to trade restrictions.

“A lot is at stake for both sides,” she said during a speech in Davos on Tuesday, adding that “our first priority” would be to negotiate.

“We will be pragmatic, but we will always stand by our principles,” she said. “We will protect our interests, and uphold our values.”

The task force had a wide remit but was heavily focused on tariffs, multiple people familiar with the group’s work said. They requested anonymity to discuss the private talks.

Olof Gill, a European Commission spokesman, confirmed the group’s existence but noted that it was operational throughout 2024 — well before the actual election — and was not officially called the “Trump task force.”

The group was headed by Alejandro Caínzos, an experienced staff member with expertise in international relations. He declined to comment for this article.

One strategic reason for keeping the work relatively quiet is that Europe appears to be trying to keep its options open.

Jörn Fleck, senior director with the Europe Center at the Atlantic Council, said the bloc was being more disciplined than it was in the first Trump administration, and “not getting drawn into political reaction cycles.”

“That’s an important learning curve that the E.U. went through,” he noted.

Europe’s planning for possible trade disruptions also comes in contrast to its behavior in the first Trump administration, Mr. Fleck said. Back then, tariffs on steel and aluminum surprised America’s allies across the Atlantic Ocean.

Even so, any preparations may have limits.

The situation in 2017 was “a much more limited threat,” said Ignacio García Bercero, a former official at the Directorate General for Trade of the European Commission who is now at the research group Bruegel. This time, Mr. Trump has threatened to impose across-the-board tariffs if he sees fit, rather than one-off levies on particular industries.

And Mr. Trump’s second-term actions could span multiple policy arenas, wrapping together energy, trade and defense goals.

In response, European countries “need to get much more creative,” Mr. Fleck said.

In some ways, Mr. Trump’s arrival is hastening changes that were already coming. Ian Lesser, who leads the German Marshall Fund’s Brussels office, noted that while Mr. Trump’s rhetoric could hasten more European military spending, that change was widely seen as needed.

“The big questions he raises only reinforce existing concerns,” Mr. Lesser said.

Still, Mr. Trump could force European policy to evolve more rapidly.

On Feb. 3, the European Council — which comprises the leaders of the 27 E.U. countries — will gather at a château outside Brussels to talk about the way forward on security matters, including issues like financing and common procurement. Notably, Prime Minister Keir Starmer of Britain will attend that event, the first time that a British premier has met with the full group since the country voted to exit the European Union in 2016.

That highlights a possibility arising from all of the looming uncertainty.

While many in Europe are worried that Mr. Trump will strike one-by-one deals with countries in Europe — cleaving the union apart — it is also plausible that pressure could draw Europe and its partners closer together.

“I think that the public will see that there is strength in negotiating as a bloc,” said Beata Javorcik, chief economist at the European Bank for Reconstruction and Development, during an interview in a Davos cafe.

Before Monday’s inauguration in Washington, François Bayrou, the French prime minister, criticized the United States for its “domineering policy” stances. But in the face of that, he said, European nations should work together.

“It’s a decision that’s up to us, the French and the Europeans,” Mr. Bayrou told reporters in Pau, a town in southwestern France where he is still mayor. “Because obviously, without Europe, it’s impossible to do it.”

Aurelien Breeden, Jenny Gross and Catherine Porter contributed reporting.

Decades of trade integration across North America are on the precipice of major disruption by tariffs that President Trump says he wants to impose on Canada and Mexico, the United States’ top trading partners.

And while tariffs are predicted to inflict pain on all three nations, they would cause more damage to Canada and Mexico, smaller economies that are deeply dependent on the United States.

Officials in both countries breathed a brief sigh of relief on Monday, when Mr. Trump stopped short of making tariffs part of his blizzard of executive orders on his first day in office. But the relief was short-lived: later in the evening, Mr. Trump told reporters he was still planning to pursue tariffs.

“We’re thinking in terms of 25 percent on Mexico and Canada,” Mr. Trump said in the Oval Office. “I think we’ll do it February 1.”

Trade experts are gauging whether tariffs will materialize or whether the threat alone is a negotiating tactic aimed at winning concessions from Mexico and Canada. Both countries avoided steep tariffs during the first Trump administration, and both are wagering that the United States needs Mexico and Canada to take on China, a much larger rival.

Economists and policymakers say tariffs would cause a loss of income and jobs and force consumers to pay more for many products.

Mr. Trump on Monday signed an executive order directing federal agencies to conduct a sweeping review of U.S. trade policies, which could result in further actions against Mexico and Canada.

The tariffs Mr. Trump is promising would most likely be met with retaliatory tariffs from Canada and Mexico and would unravel closely integrated production lines and supply chains across North America.

More than $1.5 trillion worth of items would be on the line — the total value of all goods traded between the United States and Canada, and the United States and Mexico. (This is the 2023 total value of these trading relationships, the most recent available, according to U.S. government data.)

Economists predict that the initial effect would be negative for all three nations, which are bound by a free-trade agreement known as USMCA (United States-Mexico-Canada).

The negative effect is tricky to translate into hard numbers: not only is it unclear exactly what items Mr. Trump would target and how Mexico and Canada would respond, but the consequences can shift over time, including a rise in inflation as goods become more expensive, loss of jobs and a chill on spending as consumers worry about diminished incomes.

And governments often intervene to lessen some of these negative effects. Canadian government officials have already said that they would consider bailing out businesses and supporting workers who are most affected.

But some industries would be swiftly disrupted: Agriculture, automobiles and energy suppliers, pillars of all three economies, would be upended by blanket tariffs.

United States

A few pockets of industry in the United States might welcome a 25 percent tariff on goods from Canada and Mexico — for example, American growers of tomatoes and other seasonal fruits and vegetables that have trouble competing with their Mexican counterparts.

But most industries would be hit hard by the economic disruption of such high tariffs.

Even groups that might prefer more protections against Mexican exports, like U.S. autoworkers, could be harmed if tariffs suddenly caused auto-supply chains to grind to a halt. Both the United Auto Workers and the United Steelworkers International Union also stretch across the U.S.-Canada border and include members in Canada, meaning they typically oppose any restrictions on Canadian exports.

Since the United States is North America’s largest economy and the least dependent on trade, the proportional effect on the U.S. economy would be less than on the Mexican or Canadian economies.

But tariffs would raise prices for consumers and add inflation. American households and businesses could expect to pay higher prices for a variety of goods subject to tariffs, including avocados, beer, steel, cars and petroleum.

Those higher prices would discourage purchases and most likely end up slowing the economy. Researchers at the Peterson Institute for International Economics in Washington estimate that a 25 percent tariff on all exports from Mexico and Canada would lower U.S. gross domestic product by about $200 billion for the duration of the second Trump administration.

U.S. industries that export to Canada and Mexico would also presumably be hurt if those countries turned around and imposed duties on U.S. goods. The Canadian government has made plans to target orange juice from Florida, whiskey from Tennessee and peanut butter from Kentucky, while the Mexican government has been drawing up its own retaliation plans.

Canada

The U.S.-Canada trade relationship is characterized by some eye-popping facts highlighting the countries’ close economic, industrial and trading ties.

Some $2.5 billion worth of goods is traded over the border every day, making it an $800 billion-a-year trade relationship.

For the auto industry, the U.S.-Canada border can often seem irrelevant, with a single vehicle crossing back and forth up to eight times before it is fully assembled.

Canada exports 80 percent of its oil to the United States, which gets half of its imported oil from Canada. And Canadian energy powers homes and businesses across the United States, especially in New England, where Quebec exports hydroelectric power.

And Canada sends other crucial commodities to the United States, like potash, which is used in fertilizer, and uranium, which is needed for nuclear energy production.

Should Mr. Trump pursue tariffs, the repercussion would depend on how extensive they are or if certain Canadian goods, like oil, might be exempt. But the fallout for Canada could be devastating.

Economists predict a 2 percent to 2.6 percent loss of economic output annually. More than a million Canadian jobs would be in jeopardy, including about half a million in the auto industry in Ontario, according to the province’s premier, Doug Ford.

If tariffs were placed on Canadian energy and Canada retaliated by limiting exports of oil, the effect would be felt across the country, particularly in Alberta, Canada’s oil-exporting hub.

Alberta’s provincial leader has rejected a federal government plan that would use oil as a lever to pressure the Trump administration into backpedaling from imposing tariffs.

Mexico

Mexico stands out among major economies for its dependence on trade with the United States, sending about 80 percent of its exports to its neighbor, with many coming from factories operating within 30 miles of the border.

Since those plants are overwhelmingly focused on serving the U.S. market, that makes Mexico far more vulnerable to tariffs than a large industrial economy like Germany that can more easily reorient its exports to an array of different markets.

Tariffs of 25 percent would be ruinous for Mexico, said Marcus Noland, executive vice president and director of studies at the Peterson Institute for International Economics.

“In effect, it would initiate a process of deindustrialization of Mexico,” he said.

Mr. Noland estimated that such tariffs could reduce Mexico’s economic output growth by about 2 percentage points, potentially resulting in large-scale factory closures and job losses. The automobile industry, which employs more than one million people in Mexico and relies heavily on complex supply chains moving parts across the border, could be especially vulnerable.

Other sectors of Mexico’s economy could come under severe pressure in the face of steep tariffs. Automobiles, computers, cables, phones and medical instruments are among Mexico’s largest exports.

Agriculture is another weak spot for Mexico, which supplies 63 percent of U.S. vegetable imports and 47 percent of its fruit and nut imports. The tariffs could hit emblematic products like avocados, which have experienced skyrocketing demand among American consumers since the United States began importing them from Mexico.

Mexico’s ability to soften the blow from tariffs is also limited because of budgetary challenges, said Kimberley Sperrfechter, an emerging markets economist at Capital Economics in London, citing a budget shortfall in 2024 that reached its highest level in decades.

One sector of Mexico’s economy that could benefit from tariffs is the tourism industry. If tariffs are imposed, the country’s currency, the peso, could weaken, Ms. Sperrfechter said, and make Mexico even more appealing to U.S. tourists, who represent the country’s largest international visitor group.

“But,” she added, “that’s unlikely to offset the hit to other sectors.”

Carlos Navarro was eating takeout outside a restaurant in Virginia recently when immigration officers apprehended him and said there was an order for his removal from the country.

He had never had an encounter with the law, said Mr. Navarro, 32, adding that he worked at poultry plants.

“Absolutely nothing.”

By last week, he was back in Guatemala for the first time in 11 years, calling his wife in the United States from a reception center for deportees in the capital, Guatemala City.

Mr. Navarro’s experience may be a preview of the kind of swift deportations coming under President Trump to communities around the United States, which is home to as many as 14 million unauthorized immigrants.

The administration, which has promised the largest deportations in American history, was said to be starting them as soon as Tuesday. In his inaugural speech on Monday, Mr. Trump promised to “begin the process of returning millions and millions of criminal aliens back to the places from which they came.”

Mr. Navarro’s situation provides a glimpse into what mass deportations could mean in Latin American countries at the other end of the deportation pipeline.

Officials there are preparing to receive significant numbers of their citizens, though many governments have said that they had not been able to meet with the incoming administration about its deportation push.

Guatemala, a small, impoverished nation scarred by a brutal civil war, has a substantial undocumented population in the United States. About 675,000 undocumented Guatemalans lived in the country in 2022, according to the Pew Research Center.

That makes it one of the largest countries of origin for unauthorized immigrants in the United States, after Mexico, India and El Salvador, and a laboratory for how mass deportations also stand to change life outside the United States.

Last year, Guatemala received around seven deportation flights a week from the United States, according to migration officials, which translates to about 1,000 people. The government has told U.S. officials that it can accommodate a maximum of 20 such flights a week, or around 2,500 people, the officials said.

At the same time, Guatemala’s government has been developing a plan — which President Bernardo Arévalo has referred to as “Return Home” — to assure Guatemalans facing deportation that they can expect help from consulates in the United States — and, in the case of detention and removal — a “dignified reception.”

“We know they’re worried,” said Carlos Ramiro Martínez, the foreign minister. “They’re living with immense fear, and as the government, we can’t just say, ‘Look, we’re also scared for you.’ We have to do something.”

Guatemala’s plan, which it shared at a meeting of foreign ministers from the region in Mexico City last week, goes beyond the immediate concerns that many governments in the region share — such as how to house or feed deportees on their first night.

It also addresses how to reintegrate deported Guatemalans back into society.

The plan, which focuses on linking deportees to jobs and making use of their language and work skills, also aims to offer mental health support for people coping with the trauma of deportation.

In practical terms, it means that when deportees step off the plane, government employees will extensively interview them, to get a detailed picture of those returning to the country, the help they need and the kind of work they could do.

Experts say Guatemala’s plan appears to reflect an unspoken expectation on the part of the Trump administration that Latin American governments not only receive their deported citizens — but also work to keep them from returning to the United States.

Historically, many people sent back to their homelands have turned around and tried to go back, “even under extreme circumstances,” said Felipe González Morales, who served as United Nations Special Rapporteur on the human rights of migrants.

According to the U.S. Department of Homeland Security, roughly 40 percent of deportations in 2020 involved people who had been deported before and re-entered the country.

The dynamic has for years been “basically a revolving door,” Mr. Martínez, Guatemala’s foreign minister, said in an interview.

Mr. Trump aims to change that.

“When the entire world watches President Trump and his administration mass deporting illegal criminals from American communities back to their home countries,” Karoline Leavitt, a spokeswoman for the Trump transition, said in an email, “it will send a very strong message not to come to America unless you plan to do it the right away or else you will be sent home.”

Already, the number of illegal crossings at the U.S. border is down drastically, with around 46,000 people attempting to cross in November, according to the U.S. government, the lowest monthly figure during the Biden administration.

The Trump administration is expected to pressure governments in Latin America to keep supporting its crackdown on migration.

But Guatemala’s plan to reintegrate the deported is not just a way of showing Mr. Trump that Guatemala is cooperating, according to Anita Isaacs, an expert on Guatemala who created the blueprint for the plan.

Ms. Isaacs said of deportees, “if you can find a way of integrating them and of harnessing their skills, then the opportunities for Guatemala are enormous.”

Until now, she said, deportees getting off a plane in Guatemala City mostly got some basics, like new identification documents, sanitary supplies and a ride to a shelter or the main bus terminal.

Instead, she proposed, Guatemala could embrace its newly returned citizens as an economic asset, including for its tourism sector.

As an example, she pointed to the case of hundreds of Guatemalans deported after a 2008 I.C.E. raid on a meatpacking plant in Iowa who had gone on to become volcano guides.

Still, there are steep challenges to encouraging deportees to stay in their homeland.

The forces that made them leave in the first place still exist, said Alfredo Danilo Rivera, Guatemala’s migration director: grinding poverty and a lack of jobs, extreme weather made worse by climate change, the threat of gangs and organized crime.

Then there is the draw of the United States, where there are not only more jobs, but workers get paid in dollars.

“If we’re going to talk about the reasons people migrate, the causes, we also have to talk about the fact that they settle there and many manage to succeed,” Mr. Rivera said.

Deportees also feel greater pressure to get to the United States than do people migrating for the first time, said the Rev. Francisco Pellizzari, the director of Casa del Migrante, the main shelter for deportees in Guatemala City.

They frequently owe thousands of dollars to smugglers and in rural Guatemala, poor people often hand over deeds to their houses or land as collateral for loans to pay smugglers, which leaves them essentially homeless if they are deported.

“They can’t come back anymore,” Father Pellizzari said.

The tougher measures imposed by the Biden administration at the border have also led smugglers, aware of the heightened risk of deportation, to offer migrants as many as three chances to enter the United States for the price of one attempt, according to Father Pellizzari and others.

José Manuel Jochola, 18, who was deported to Guatemala last week after being apprehended for illegally crossing the border into Texas, said he had three months to use his remaining chances. “I’m going to try again,” he said, though he would wait to see what Mr. Trump did.

The desire to go back to the United States after being deported is particularly strong among those whose families are there.

Mr. Navarro, the man recently deported from Virginia, said he was undeterred by Mr. Trump’s crackdown. “I have to go back, for my son, for my wife,” he said.

A woman who was on Mr. Navarro’s deportation flight, Neida Vásquez Esquivel, 20, said it was her fourth time being deported while trying to reach her parents in New Jersey. Another attempt was not out of the question, she said.

But some deportees say the greatest appeal of staying in Guatemala is that, for now, the alternative no longer looks as good.

After José Moreno, 26, was deported last week after a drunken-driving accident, he decided not to try to go back to Boston, where he spent a decade, because of the perils of crossing the border and the new president’s attitude toward immigrants.

Instead, he said, he would use his English to offer guided tours in Petén, an area in Guatemala with a picturesque lake and Mayan ruins, where his family has a small hotel.

“My parents are here, I have everything here,” he said. “Why would I go back?”

Jody García contributed reporting from Guatemala City, and Miriam Jordan from Los Angeles.