The flow of natural gas through a major pipeline from Russia to Europe was cut off early Wednesday after Ukraine refused to renew an agreement that allowed for the transit of Russian gas through its territory.

President Volodymyr Zelensky of Ukraine had warned for months that he would not renew the prewar contract, which expired at midnight on Dec. 31, because of Russia’s full-scale invasion of Ukraine.

Kyiv’s decision to suspend the flow of gas through a pipeline that had carried Soviet and then Russian gas to Europe for decades is part of a broader campaign by Ukraine and its Western allies to undermine Moscow’s ability to fund its war effort and to limit the Kremlin’s ability to use energy as leverage in Europe.

“This is a historic event,” Ukraine’s energy minister, Herman Galushchenko, said in a statement. “Russia is losing markets, it will suffer financial losses.”

The pipeline through Ukraine, built in the Soviet era to carry Siberian gas to European markets, is Russia’s last major gas corridor to Europe following the 2022 sabotage of the Nord Stream pipeline to Germany, possibly by Ukraine, and the closure of a route through Belarus to Poland.

The Kremlin-controlled energy giant, Gazprom, issued a statement early on Wednesday confirming that it was no longer sending gas through the pipeline. President Vladimir V. Putin had signaled in a Dec. 19 news conference that the agreement would not be extended. “That’s fine — we will survive, Gazprom will survive,” he said.

Because the expiration of the deal was long anticipated and prepared for by European countries, it was not expected to have a substantial effect on prices, analysts said.

While the move could reduce Russia’s revenue from gas sales by about $6.5 billion a year, it also carries risks for Ukraine. Moscow could decide to bomb Ukraine’s network of pipelines, which it has largely spared from attack so far, now that it has little incentive to leave them unharmed, military analysts said.

At its peak, Russia supplied nearly 40 percent of imported gas consumed in Europe, but that has fallen sharply in the past three years. The pipeline through Ukraine accounted for only about 5 percent of Europe’s gas imports last year.

Moscow cut gas supplies to Europe after invading Ukraine in 2022, pushing up energy bills and forcing many governments to unveil emergency packages to help struggling businesses and citizens. In response, most European Union member states reduced their reliance on Russian gas, although three countries — Austria, Hungary and Slovakia — continued to buy large amounts of energy from Russia.

The Austrian government said in a statement Wednesday that it had prepared in advance and found suppliers outside Russia. “We did our homework and were well prepared for this scenario,” said Leonore Gewessler, Austria’s energy minister, on social media.

While Hungary had pushed for the Ukrainian pipeline to remain open, it receives most of its Russian gas via the TurkStream pipeline, which runs from Russia under the Black Sea to Turkey.

Slovakia, whose prime minister, Robert Fico, is friendly with Mr. Putin, is heavily reliant on Russian gas, but its economy minister said in a statement Tuesday that it would not face shortages because of gas in storage facilities and alternative supplies.

Mr. Fico, who traveled to Moscow last month for talks with Mr. Putin focused on gas, had threatened to cut off electricity supplies in retaliation against Ukraine if it did not extend the transit deal. On Wednesday he said that the agreement’s end would have “a drastic impact on us all in the EU but not on the Russian Federation.”

Most vulnerable is Moldova, a small country sandwiched between Ukraine and Romania. In December it declared a state of emergency amid fears that the end of Russian gas traveling through Ukraine would endanger its main source of electricity, a gas-fueled power plant in the breakaway Russian-speaking region of Transnistria.

Gazprom warned Moldova this week that it would halt all gas deliveries on Jan. 1 even if the pipeline through Ukraine kept working, citing a long-running dispute over unpaid bills. Immediately hit by the shutdown was Transnistria, a sliver of Moldovan territory next to Ukraine that, with support from Moscow, declared itself an independent microstate after the collapse of the Soviet Union.

The energy company there told its customers Wednesday that it would stop supplying gas for heating to private houses. The company would provide gas for cooking “until the pressure in the network drops to a critical level,” it said in a statement on Telegram.

That Russia would risk hurting its own proxies in Transnistria, which has been occupied by Russian troops for more than three decades, is a measure of how the war in Ukraine has altered Moscow’s priorities.

Ukraine, too, has faced difficult choices. Struggling to withstand relentless Russian assaults both on the front and directed at its energy grid, Kyiv appears to have decided that an opportunity to deliver an economic blow to the Kremlin by reducing its earnings from gas exports outweighed the potential risks.

“We won’t allow them to earn additional billions off our blood,” Mr. Zelensky said when he announced the decision on Dec. 19 to shut down the pipeline. On Wednesday, he wrote on social media: “As a result of Russia weaponizing energy and resorting to cynical blackmail of partners, Moscow lost one of the most profitable and geographically accessible markets.”

The move “underscores just how much the European political and energy landscape has changed since Russia launched its full-scale invasion of Ukraine in 2022,” Bota Iliyas, a senior analyst at Prism, a strategic intelligence firm, said before the shutdown.

Mr. Fico’s trip to Moscow earlier in December was a blow to European unity in keeping the Kremlin isolated. As soon as Mr. Fico returned to Slovakia, he threatened to cut Ukraine off from vital energy supplies it needs to sustain its battered power grid. About 19 percent of the electricity Ukraine imports from the European Union flows through Slovakia, according to Ukrainian officials.

Mr. Galushchenko, Ukraine’s energy minister, said that halting electricity supplies to Ukraine would violate European regulations, and Kyiv has issued an appeal to Brussels to block the move. At the same time, Ukraine is negotiating with other European allies, including Poland, to import more power and offset any action Slovakia might take.

Ukraine has been working to decrease its own dependence on Russia to meet its energy needs and recently announced that it had imported liquefied natural gas from the United States, via Greece, for the first time.

Mike Ives contributed reporting.

More than 50 tanks and military vehicles lay scattered and abandoned across the parade and training grounds of an army base in northern Syria, captured by rebels in their lightning-fast offensive that toppled President Bashar al-Assad.

The main garrison building bore the marks of two large explosions, but little sign of close-contact fighting. The assault was over in a day when the Syrian soldiers retreated, said Abu Muhammad, a rebel fighter guarding the base.

The government soldiers left behind a filthy jumble of army life: clothes, blankets, gas masks and helmets, and empty tin cans. Living conditions were primitive, with no windows or doors — instead, sacks or sheets of tin roofing were fixed over openings.

The base reflected the opportunity for a new government borne out of a well-prepared military campaign, bringing together different rebel groups, whose success surprised even its own fighters. But it also was a measure of the challenges ahead as they look to rebuild a country broken by more than a decade of civil war, depriving and depleting its military.

The country’s new leadership recently announced a plan to unite the various rebel factions under one government and for their armed fighters to serve together in one army.

In interviews with dozens of combatants, many said they had already accepted a single command under Ahmad al-Shara and his rebel force, Hayat Tahrir al-Sham, and had benefited from uniting their forces.

“The important thing is to be together,” said Nasr al-Nahar, 41, a senior rebel commander who said his own group had settled its differences with Hayat Tahrir al-Sham. “We are fighting together for liberation.”

But bitterness and divisions are likely to continue with forces that remain in opposition, including the Kurdish militia that controls much of northeastern Syria; the Islamic State extremist group, which operates in parts of central Syria; and remnants of Mr. al-Assad’s security forces who have shown signs of resistance.

While the rebels are taking over security of the country and its borders, they are inheriting a devastated military infrastructure that will be hard to capitalize on or rebuild.

A 10-day journey along the path of the rebels’ advance by a reporter and a photographer for The New York Times and a Syrian translator showed that the Syrian Army they defeated — and are now replacing — was so ill-equipped and demoralized that its soldiers had laid down their arms or fled in panic.

The rebels breached defenses that had held strong for years, encircling and assaulting military garrisons often without much of a fight. The tank base, which fell on the second day of the operation, was decrepit, its windowless buildings barricaded with a makeshift protection of tractor tires and metal drums filled with earth.

On other bases and checkpoints near the former front line, Syrian soldiers clearly lacked resources. They had dug a makeshift bunker inside a farm building, heaping rubble on top of sheets of corrugated iron to provide protection from shelling, and had patched up shell holes in the walls with a mixture of mud and straw.

“We started the operation thinking we would take only one village, and we took all of Syria,” said a Hayat Tahrir al-Sham fighter, Abu Aisha, with a wide grin.

The 24-year-old was hanging out with a fellow fighter, Abu Hamza, 25, in the central park of the city of Hama, lending his assault rifle to local youths to pose with it for photographs. Both men said they had been training and fighting since they were 15 and would readily join the national army.

Some of the fighting during the rebel offensive was intense. Abu Aisha said his commander and deputy commander were killed at a main intersection in the first days of the operation. Others were killed and wounded in airstrikes.

But rebel fighters said that they had encountered weaker resistance than in previous years of fighting. Russian air power and Iranian-backed militias on the ground, which in the past had provided much of the glue that held the Assad regime together, had been reduced in recent months.

Aleppo fell to the rebels on Nov. 30 after just three days of fighting.

A fabled city centered around an ancient citadel, Aleppo was the site of grueling fighting when the 2011 peaceful uprising spiraled into civil war. It had taken Mr. al-Assad four years to wrest control of the city from the rebels in 2016, and then only with the help of Iranian militias and Russian troops. Its sudden fall stunned the Syrian leadership.

“It was serious from the moment Aleppo fell,” said Abed, 39, a Syrian police officer, who gave only his first name for fear of reprisals.

“There was no command,” he added. “The silence was clear.”

After Aleppo, the rebels pushed southward to attack the cities of Hama and then Homs, with the capital, Damascus, already in their sights.

On the roads along the way, tanks and armored vehicles were left abandoned, had crashed or had broken down. Few of them showed signs of fighting, such as being burned in explosions or bearing bloodstains from casualties.

There were some indications of panic. An armored personnel carrier had smashed into the corner of a house in a village, and a tank lay upside down where it had crashed into a trench.

As the rebels advanced, two soldiers, Mahmoud, 23, and his brother Mamdur, 26, serving in separate Syrian Army bases, prepared to desert. The brothers asked that their surname not be published to avoid repercussions.

Mahmoud escaped when rebels attacked his base in the southern region of Golan. He ran through a forest with three other soldiers and sheltered in a village for two nights until their host told them that Mr. al-Assad had fallen.

On Dec. 7, Mamdur heard an order come over his senior officer’s radio to evacuate the base. The soldiers changed into civilian clothes, left their weapons and rode in a truck to the provincial capital.

At a checkpoint, rebel fighters searched him for weapons but then told him, “Just go home,” he recounted. “They knew everyone was running away.”

Poor conditions, low pay and disaffection all played a role in the Syrian military’s collapse, the two soldiers said.

“They did not fight,” said Mahmoud, who was conscripted into the army 18 months ago. “No one loves Assad, but no one could say it.”

“Assad forced us into the army,” he added. He had wanted to continue his studies but was ordered into the military, where he received a salary of $10 a month. His brother was forced to stay in the army for five and a half years, he said.

The soldiers were happy to be home. The police officer was wary of the new group in charge.

But the rebel commander, Mr. al-Nahar, was optimistic. Hayat Tahrir al-Sham fighters cared about the future of the nation, he said. “Most of them are for Syria, and I respect them,” he said.

He added that he hoped the new government could work out an agreement with the Kurdish group, too.

For many, the promises made during the rebel’s campaign provide hope about the potential for the future — even if it remains to be seen whether the new government makes good on them.

Importantly, for the new leadership, the rebel campaign was successful because it reached out to communities in the government-controlled parts of Syria and was in touch with people inside the regime’s structures, said Ammar Kahf, the executive director of the Omran Center for Strategic Studies in Istanbul.

Their promise that members of minority groups would not be harmed and a call for members of the security services to lay down their weapons sharply reduced the level of conflict, he said.

In the end, Mr. al-Assad’s grip on the country was anchored by the fear his regime instilled in the population, the Syrian police officer, Abed, said.

“We hate Assad, and we like life,” he said.

Ronen Bergman contributed reporting from Tel Aviv.

Airstrikes by Pakistani warplanes inside Afghanistan have intensified tensions in recent days in an already volatile region. Once-close ties between Pakistan’s leaders and the Afghan Taliban have frayed, and violent cross-border exchanges have become alarmingly frequent.

Officially, the Pakistani government has been tight-lipped about the strikes in Afghanistan on Dec. 24. But security officials privately said that the Pakistani military had targeted hide-outs of Tehreek-e-Taliban Pakistan, a militant group also known as the T.T.P. or the Pakistani Taliban that has carried out a series of terrorist attacks inside Pakistan.

The security officials said that several top militants from the Pakistani Taliban had died in the airstrikes, which came days after 16 Pakistani military personnel were ambushed and killed in a border district.

The Taliban regime in Afghanistan said that dozens of civilians had died in the strikes, including Pakistani refugee families. The group condemned the strikes as a blatant violation of Afghan sovereignty, and said it had retaliated by conducting attacks on “several points” inside Pakistan.

Officials in Pakistan have not officially commented on those attacks. But they reported that they had thwarted a cross-border incursion by militants they said had been facilitated by the Taliban authorities.

The airstrikes were the Pakistani military’s third major operation on Afghan soil since the Taliban’s return to power in August 2021, and the second in the past year alone.

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Crispín Agustín Mendoza had just announced he was running for mayor of Alcozauca, a remote hamlet in the strife-torn mountains of southwest Mexico. Then, in the middle of the night, the gunmen arrived.

His wife and children screamed in fear as the men sprayed their home with gunfire in a failed bid to kill him. Undeterred, Mr. Mendoza stayed in the race and won. He is among the politicians who somehow survived assassination attempts this year in one of the most violent election cycles in Mexico’s recent history.

But Mr. Mendoza stands out for another reason. Smuggled as an adolescent into the United States, he lived undocumented in Silicon Valley’s shadow economy well into adulthood, only to follow his star back to Mexico, start his own thriving business and try his hand at politics.

Now, he is getting a frontline glimpse of the cartel turf battles overwhelming Guerrero, a Mexican state of 3.5 million known for exceptionally brutal attacks on public officials in recent weeks: like the beheading of the mayor of the state capital, Chilpancingo; and the fatal shooting of a judge in Acapulco in broad daylight.

“You have to assume one day you’ll be attacked and killed,” Mr. Mendoza, 41, said nonchalantly in lightly accented English, which he frequently peppers with Californian slang, during a recent interview in Alcozauca’s Town Hall.

A security detail of six soldiers accompanies Mr. Mendoza 24 hours a day. He faces both the challenge of staying alive and political shifts in the United States that could potentially upend towns like his own.

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There’s a good chance that many first-time visitors to the Trevi Fountain in Rome know the drill. To ensure a return to the Eternal City, the legend goes, stand with your back to the water and toss a coin with your right hand over your left shoulder.

The ritual became famous around the world thanks to the 1954 film “Three Coins in the Fountain,” and its eponymous song — recorded by Frank Sinatra — which won the Oscar for best original song.

The coin throw is such a popular item on tourist itineraries that even a recent three-month restoration that cut off direct access to the 18th-century fountain was not a deterrent. Visitors still crowded in front of the transparent panels protecting the work site to lob coins — about 61,000 euros’ worth, or $63,000 — into a squat utilitarian tub.

“The tourist is going to toss a coin, they don’t care about construction or no construction,” Fabrizio Marchioni said on a chilly December morning a few days before the fountain’s reopening.

He should know.

For 13 years, Mr. Marchioni’s principal job for the Roman Catholic charity Caritas has been to collect and count the coins tossed into the fountain.

“These are coins of solidarity,” as “they’re put to good use,” said Giustino Trincia, the director of Rome’s Caritas branch. More than 52,800 meals were doled out at Caritas soup kitchens in Rome in 2023, just one of many projects the charity runs.

The coins are claimed by Rome’s municipal administration, but it has donated them to Caritas since 2005. The proceeds in 2023 were close to 2 million euros.

The recent cleanup of the fountain, 10 years after a major restoration, came just in time for the start of the Catholic Church’s Jubilee Year on Christmas Eve. With some 32 million visitors expected over the next year, Rome is in a state of busy preparation, with dozens of monuments being cleaned and polished.

The fountain’s temporary closure also allowed city officials to test out controlling visitor access. At the reopening, just before Christmas, officials announced that only 400 people at a time would be allowed into the sunken area in front. Visitors will enter at one end of the basin and exit on the other side, with monitors keeping watch during daytime hours.

“The goal is to allow everyone to enjoy the fountain to the fullest without the crush, without confusion,” Roberto Gualtieri, the mayor of Rome, said at the reopening. The city is also considering charging a nominal fee, he said.

Rome has a plethora of fountains, the public, decorative faces of aqueducts that were originally built by the ancient Romans, but none match the fame of the Fountain of Trevi. In the early 18th century, “a practically unknown architect,” Nicola Salvi, replaced a more modest iteration of the fountain with the monumental work that reaches nearly 115 feet in height, arguably “the best known monument of modern Rome,” said Claudio Parisi Presicce, Rome’s superintendent for cultural heritage.

Celebrated in a symphony, as well as in artworks over the centuries, the fountain became a cinematic star in the 20th century, most famously in Fellini’s “La Dolce Vita,” where Anita Ekberg throatily called to Marcello Mastroianni to join her as she waded in its waters (an act that would be much frowned upon in real life).

Fresh fame came via the 2024 season of Netflix’s series “Emily in Paris,” after the protagonist, Emily Cooper, made the fountain one of her first Roman stops.

The coin-tossing ritual began at the end of the 19th century, when German academics studying in Rome reprised an ancient Roman practice of throwing coins into water for good luck. It quickly caught on.

Over the decades, the coins — and people sitting on the marble edge of the fountain (another definite no-no) — have contributed to its wear and tear, especially as visitor numbers have risen sharply in recent years.

“These are magnificent, enormous monuments, but they are very delicate,” said Anna Maria Cerioni, who has overseen many of Rome’s fountains for three decades in her role as head of restoration for the city’s art superintendency.

The minerals in the coins often leave marks on the product used to waterproof the basin. Specially developed for the fountain, it is known as “Trevi White,” and periodic maintenance is necessary.

The fountain is still supplied by the Aqua Virgo, built in the first century B.C.E. and the only one of the 11 aqueducts built by the ancient Romans that has remained almost constantly in use, said Marco Tesan, who oversees the maintenance of some of Rome’s fountains and aqueducts for the water and electricity utility ACEA.

Twice a week, the utility’s workers use a machine developed for swimming pools to suck up the coins from the basin. During the maintenance phase, brooms and dustpans sufficed, “though you still feel achy at the end of the day,” said Luca Tasselli of ACEA.

At the fountain, the collected coins are weighed under the oversight of city police officers before Mr. Marchioni takes them to Caritas offices. There, they are first washed under tap water, then laid out on a towel-lined table so that impurities can be removed. Along with other stuff.

Larger objects commonly found in the fountain, like bottles, umbrellas, fruit and drinking glasses, are removed directly by ACEA workers. Mr. Marchioni and the volunteers who help him root out smaller items.

Recently found: religious medals, guitar picks, subway tokens, keys, marbles, shells, and pins of all shapes and sizes. Bracelets and rings were also common, and Mr. Marchioni surmised that they might have fallen off during particularly enthusiastic tosses.

Expensive-looking jewelry is turned over to the police.

Because there isn’t a market for coin-drying machines, Caritas tasked a company that makes machines to dry cutlery with converting one for its purposes. The coins are dried and then passed through a machine that separates euro coins from everything else. It’s so sophisticated that it even detected a bunch of fake two-euro coins that were making the rounds in May and June.

Foreign currency is sent to a company to exchange, which can get troublesome, said Mr. Marchioni. “Let’s say that tossing euro coins is best,” he said.

The proceeds are used for a variety of projects, from youth activities to care programs for people with Alzheimer’s disease. Mostly, Caritas helps needy families make ends meet, reaching almost 10,000 people in 2023, said Mr. Trincia of Caritas.

He added that he hoped tourists visiting Rome were aware of the good they are doing through the fountain. “Poverty doesn’t go on holiday,” he said.

Ivory Coast has announced that French forces will withdraw from its territory, following in the footsteps of several other West African countries and further reducing France’s waning power in the region.

French troops will leave Ivory Coast this month after handing over a military camp in a suburb of the country’s capital, President Alassane Ouattara said in an address broadcast to the nation Tuesday night.

France, a major former colonial power in Africa, confirmed the withdrawal, which follows similar announcements from West African countries, most recently Chad and Senegal.

France’s military presence in Africa will soon be limited to troops in Djibouti and Gabon — a far cry from its many troops that were stationed in the Sahel fighting jihadists just three years ago.

Mr. Ouattara said that the Ivorian Army had been modernized to such a degree that French troops, of which there were about 600 in the country, were no longer needed.

“We can be proud of our army, whose modernization is now complete,” he said in a New Year’s Eve address to the nation. “It is in this context that we have decided on the coordinated and organized withdrawal of French forces from the Ivory Coast.”

In recent years, there has been a sharp rise in criticism of France in its former African colonies, with many accusing the French of neocolonialist business practices and patronizing attitudes.

In Africa’s coup belt, a string of countries whose governments have been toppled in recent years, the ruling military juntas have leaned in to this criticism to rally public opinion.

In Senegal, where the president asked Paris to remove its troops in November, rhetoric about reclaiming “sovereignty” from France was used to great effect by opposition leaders who tapped into widespread youth discontent, decisively winning a nail-biting election last March.

But Ivory Coast is different. Mr. Ouattara has long been widely seen there as France’s man, after his predecessor, Laurent Gbagbo, was forcibly removed from power in 2011 with the help of French military strikes.

As France’s alliances in the region have crumbled, Mr. Ouattara has remained standing, becoming the country’s staunchest African ally.

In 2020, Mr. Ouattara won a third term, despite the Constitution of Ivory Coast limiting presidents to two terms. Now 83, he has not yet said whether he intends to seek a fourth term in presidential elections later this year.

But some analysts saw his announcement about the French troop withdrawal as an attempt to garner support from a public that has become increasingly critical of the French military presence, which is seen as a violation of sovereignty.

Over the past year, President Emmanuel Macron of France’s special envoy to Africa, Jean-Marie Bockel, has been leading a mission to change France’s military profile and mission in Africa, in the context of its changing relationship with the continent.

In February, during a trip to Ivory Coast, Mr. Bockel said that the French military base there needed to be “remodeled.”

France must now coordinate a withdrawal from at least two countries at once, as its troops began leaving Chad late last month. President Bassirou Diomaye Faye of Senegal has not set a precise date, but he said on Tuesday that there would be no military presence there “from 2025.”

Three countries near Ivory Coast that have forced out French troops — Mali, Burkina Faso and Niger — have expressed skepticism about the exit of French troops from the region. Instead, they have cast the departures as “trickery” on the part of France’s government, which they call the “imperialist French junta.”

In a recent joint statement, the military rulers of the three countries said that closing military bases was merely an attempt to make France’s “neocolonial inclinations” less visible.

In an email on Wednesday, a spokesperson for the French Defense Ministry said that the withdrawal of troops did not “call into question the excellence of the bilateral military relationship.” The spokesperson added: “The cooperation plan between the two armies remains. It is based on mutual trust and the wealth of operational interactions.”

Even without troops on the ground, France will continue its efforts to counter the spread of terrorism from the crisis-hit Sahel region to West Africa’s coastal nations, one of which is Ivory Coast.

France and Ivory Coast jointly founded an international counterterrorism academy there in 2021. Several Western nations are supporting the academy, including the United States, which also has a small contingent of military personnel in the country.

Elian Peltier and Richard Fausset contributed reporting.

Displaced Gazans largely entered the new year on Wednesday shivering in tent camps or taking refuge in schools-turned-shelters as Israel’s war with Hamas neared its 16th month.

At least five people were killed in an Israeli strike in the northern Gaza Strip before dawn in the northern city of Jabaliya, according to the Palestinian Civil Defense, an emergency service overseen by the Hamas-run Interior Ministry, which does not distinguish between militants and civilians in its reporting.

The Israeli military said fighter jets had bombarded a “terrorist structure” in an attempt to target Hamas militants within it. In a statement, the Israeli military said it had taken precautions to avoid harming civilians.

As the war ground on, Yoav Gallant, the former Israeli defense minister who helped oversee his country’s military campaign in Gaza for more than a year until he was fired in November by Prime Minister Benjamin Netanyahu, said in a televised statement that he was stepping down from his seat in Parliament.

Mr. Gallant said his insistence that the military begin conscripting ultra-Orthodox citizens, who have long been exempted from mandatory service, had been behind his dismissal. Since then, he said, Mr. Netanyahu has rushed through a conscription bill that still exempts too many and won’t meet Israel’s security needs.

“That I cannot accept and be a partner to,” Mr. Gallant said.

His resignation came as mediators were trying to secure a cease-fire deal that would free the remaining Israeli hostages seized by Hamas-led militants during their Oct. 7, 2023, attack. Israeli officials have said they want a deal that secures freedom for at least some hostages but allows Israel to continue fighting in Gaza if it deems it necessary. Hamas has refused any agreement that does not include an end to a war that has decimated the enclave and unleashed a prolonged humanitarian crisis.

More than a year into the war between Israel and Hamas, many Gazans are living in makeshift tents, and finding enough food and clean water has become a daily ordeal. Over the past few days, Gazans have endured chilly winter rainstorms; Gazan officials say some infants have died from the cold.

In the southern city of Khan Younis, Awad Abid, a displaced taxi driver, spent the past two days huddling with his children in a half-flooded tent. Mr. Abid said he was barely able to purchase enough flour to keep them fed, let alone buy new blankets and coats.

“Tonight we’ll cover ourselves in blankets that are still drenched in water, because the sun was too weak to dry out,” he said.

In northern Gaza, Israeli ground forces have been fighting for almost three months against what Israel says is a renewed Hamas insurgency. Repeated Israeli offensives have turned the area into a landscape of vacant, torn-up streets and ruined buildings.

The fighting in the north has displaced more than 100,000 people, and on Wednesday night the Israeli military again ordered residents remaining in parts of the area to leave for Gaza City. The Israelis said that they would soon begin operations in response to Hamas rocket fire.

Aid groups have lamented the deteriorating humanitarian situation in northern Gaza. Israel says it is allowing enough supplies to enter the area, although government attorneys conceded in a December court filing that the Israeli military might have initially underestimated how many people remained there.

Montaser Bahja, an English teacher from Jabaliya, said he was lucky enough to find an empty apartment in Gaza City to shelter with his family. In a vain effort to keep out of the cold, he spread plastic wrap over the frames of windows shattered in the fighting.

During a rainstorm, Mr. Bahja said, the near-constant sound of Israeli airstrikes slowed to the occasional distant blast. But then on New Year’s Eve, as the downpour began to let up, the bombardment resumed across northern Gaza, he said.

“We hoped that by the new year, the war would end,” said Mr. Bahja. “Instead, there was bombing all night.”

At least 45,000 people have been killed in Gaza since the Hamas-led attack on Israel last year prompted the war, according to the Gaza Health Ministry, which does not distinguish between civilians and combatants. Hamas’s Oct. 7 assault killed around 1,200 people in Israel, and 250 people, mostly civilians, were taken hostage, according to Israel.

Officials and mediators had voiced tentative optimism last month that the negotiations for a cease-fire deal that would bring about 100 hostages still in Gaza, an unknown number of whom are believed dead, back to Israel could move forward. They pointed to a weakened Hamas that might be more willing to make concessions and to increased pressure by the incoming Trump administration on both sides.

But a deal has yet to emerge, despite last-ditch attempts by President Biden’s advisers to reach one before he leaves office.

For Gazans, the reports of progress brought a surge of optimism — quickly followed by yet more crushing disappointment as the talks appeared to stall.

“We looked through Facebook at videos of everyone abroad happy and celebrating the new year with their children,” said Mr. Abid. “Meanwhile, we’re still being bombed and hungry and cold.”

Ephrat Livni contributed reporting.

Hoping to bolster the resolve of a nation whose heart “is covered in scars” after more than 1,000 days of unrelenting Russian assaults, President Volodymyr Zelensky of Ukraine said in his New Year’s address on Wednesday that he believed the United States would continue to stand with Kyiv in “compelling Russia into a just peace.”

He also reiterated his vow that his country would never give up on the goal of making Ukraine whole again.

“One day, Ukraine will return to be together,” Mr. Zelensky said, addressing Ukrainians living under Russian occupation in Crimea, the eastern Donbas region and the southern cities of Melitopol and Mariupol.

Despite his expression of confidence, Mr. Zelensky faces an uphill fight, not just on the battlefield, but also diplomatically.

Even Mr. Zelensky has acknowledged that it might not be possible to oust Russia solely by military means from all of the roughly 20 percent of Ukraine that it currently occupies. But he reiterated that diplomatic pressure from the West could ultimately help repel the Russian offensive led by President Vladimir V. Putin.

President-elect Donald J. Trump’s intentions for Ukraine are unclear. He has said that bringing the war to a quick end will be a priority of his administration but has not offered details on how that can be achieved. He has long made his admiration for Mr. Putin known, and has previously expressed disdain for Ukraine.

Still, Mr. Zelensky said he had “no doubt that the new American president is willing and capable of achieving peace and ending Putin’s aggression.”

Russia has also repeatedly stressed its conditions for any negotiations. This week, Foreign Minister Sergei Lavrov reiterated Russia’s demand that Ukraine renounce its right to sovereignty and territorial integrity as a precondition to start peace talks. He told the Russian news agency TASS that it would not enter into any negotiations unless Ukraine renounced its objective of re-establishing its internationally recognized 1991 borders, an area that includes Crimea and the Donbas region.

Mr. Zelensky said in his address that peace could come only when Ukraine was militarily strong enough to force Mr. Putin into negotiations. Currently, Russia maintains the initiative across the front, grinding out costly but consistent gains as Ukraine struggles to stabilize its defenses.

On Wednesday, Russia’s forces continued to close a pocket of resistance around the Ukrainian town of Kurakhove in the southern Donbas region, advancing to an industrial plant on the far western edge of the town, according to analysts who track movements on the battlefield using combat footage.

Russian soldiers released videos showing themselves holding flags at the facility and claiming control of the town, but Ukrainian officials said that pitched battles were still being fought at the plant and that the struggle for control was still playing out.

In his address, Mr. Zelensky acknowledged the many challenges Ukraine is facing but said that national unity remained its most potent asset.

“We overcame everything 2024 brought together,” he said. “Victories and setbacks. Joys and challenges. Tears of happiness when we succeeded. And tears of pain when our hearts were wounded.”

Although about a third of the weapons Ukraine used on the battlefield in 2024 were produced domestically, its hope of victory depends on the resolve of its allies, he said.

Mr. Zelensky’s 20-minute address came against the backdrop of wailing air-raid alarms as the new year began much in the same way the old year ended — with Russian drones and missiles streaking across the sky over cities across Ukraine.

In Kyiv, the capital, wreckage from one drone fell on a residential building only a few minutes from the Presidential Office, partly destroying the residential building’s top two floors and causing a fire, according to Ukrainian emergency services. Two people were killed and seven others were wounded across the city, local officials said.

Russian missiles and drones targeted Kyiv almost 200 times in 2024, and air-raid alarms sounded more than 500 times, according to city officials.

In those attacks, Russia launched over 1,300 strike drones, 200 cruise missiles, 24 ballistic missiles, 22 Kinzhal aeroballistic missiles and seven hypersonic Zircon missiles, Ukrainian military officials said. Many of those attacks were directed at energy infrastructure, but Russia also damaged almost 550 residential buildings in the capital, leaving almost 120 people homeless, city officials said.

Those numbers represent only a fraction of the attacks across the country, and the Ukrainian Air Force said that Russia had launched “significantly more” missiles and drones in 2024 than in the previous year.

Kyiv is far better protected than many other Ukrainian cities that are routinely hit, and the air force warned that the Kremlin had the capability to expand its campaign to shatter Ukraine’s energy grid and punish the Ukrainian public.

Mr. Zelensky said that those same missiles would threaten other nations if Russia were not stopped in Ukraine. And he warned against misguided hope.

“If Russia shakes your hand today, it does not mean that tomorrow it will not start killing you with the same hand,” he said.