In Britain, a languishing prime minister is suddenly a statesman, while his up-and-coming populist rival has been thrown on his heels. In Canada, the incumbent Liberal Party has a chance to win an election long thought out of reach. In Germany, the incoming center-right chancellor is dominating the agenda after an election many feared would be a breakthrough for the hard right.

As President Trump’s “shock and awe” policies radiate around the world, they are reshaping global politics in unforeseen ways.

Mr. Trump’s sweeping tariffs and threats to the trans-Atlantic alliance have breathed life into centrist leaders, who are regaining popularity for their willingness to stand up to the American president. His clash with Ukraine and tilt toward Russia have thrown right-wing populists from Britain to Germany off balance, blunting, for the moment, their efforts to capitalize on Mr. Trump’s restoration to the White House.

“One of the great ironies of Trump is that he turns out to be the great unifier of Europe,” said Constanze Stelzenmüller, an expert in trans-Atlantic relations at the Brookings Institution in Washington. “It is impossible to overstate how shocked Europeans are by what’s happening.”

The “Trump bump” goes beyond Europe. In Mexico, President Claudia Sheinbaum has won praise, and stratospheric poll numbers, for her coolheaded handling of Mr. Trump’s tariffs. Mark Carney, a former central banker, was catapulted to the leadership of Canada’s Liberal Party with 86 percent of the vote on the belief that he can manage a trade war with the United States.

Mr. Carney’s party, which lagged the Conservatives by double digits under the premiership of Justin Trudeau, has recently closed the gap, putting the Liberals within striking distance of a victory in an election that Mr. Carney is expected to call soon. The Conservative leader, Pierre Poilievre, has struggled to regain momentum, and Liberals have been quick to paint him as a Canadian Trump.

In Europe, which has appeared vulnerable to the same populist tide that swept Mr. Trump back into power, the president’s policies have steadied mainstream leaders who were struggling with stagnant economies and restless electorates. Facing down American tariffs and drawing together to confront an ally that is behaving more like an adversary has proved to be good politics.

Prime Minister Keir Starmer’s whirlwind of diplomacy — trying to marshal a European peacekeeping force for Ukraine while also working to salvage the alliance with Washington — has won praise across the political spectrum in Britain. Mr. Starmer’s poll numbers have bounced back from what was a dismal first six months in government, though he is still underwater in net approval ratings.

“He desperately needed something, and this appears to be it,” said Tim Bale, a professor of politics at Queen Mary University of London. “It’s not nothing if a prime minister performs well on the world stage.”

Equally significant, Nigel Farage, the populist leader of the insurgent, anti-immigration party Reform U.K, has stumbled for the first time since he won election to the British Parliament last July.

Mr. Farage, a longtime Trump ally, has struggled to fend off accusations that he sympathizes with President Vladimir V. Putin of Russia. He criticized President Volodymyr Zelensky of Ukraine for not wearing a suit to his meeting with Mr. Trump at the White House, even amid signs that the British public overwhelmingly sided with Mr. Zelensky in his clash with the American president.

Mr. Farage’s party was thrown into turmoil last Friday after it reported one its own lawmakers, Rupert Lowe, to the police for threatening a senior colleague — an allegation that Mr. Lowe denies.

Mr. Farage, analysts said, might feel threatened because Elon Musk, the billionaire who is Mr. Trump’s close ally, praised Mr. Lowe in January while withdrawing his endorsement of Mr. Farage, saying he “does not have what it takes.” Mr. Lowe complained in a recent newspaper interview that under Mr. Farage’s leadership, Reform has become a “protest party led by the Messiah.”

“To some extent, Farage has made himself quite vulnerable,” Professor Bale said.

In Parliament last week, Mr. Starmer won raucous whoops and cheers from Labour and Conservative backbenchers alike when he scolded Mr. Farage for his history of friendly statements about Mr. Putin and reaffirmed Britain’s steadfast support for Ukraine.

“Zelensky is a war leader whose country has been invaded,” Mr. Starmer said, as a chastened-looking Mr. Farage nodded in agreement. “We should all be supporting him and not fawning over Putin.”

Tying Mr. Farage to Mr. Putin, analysts said, is more effective than going after him as an enemy of the political system, since like other populist politicians, he thrives on being vilified by the establishment.

“The strategy that has not worked is to point at the populists and say they are the enemy,” said Ben Ansell, a professor of comparative democratic institutions at the University of Oxford. “What works much better is to point at an external enemy and try to lash them to that enemy.”

Mr. Farage’s alliance with Mr. Trump is also becoming a burden, Professor Ansell said, not just because the president is unpopular in Britain but also because his chaotic approach to governing deprives his allies abroad of conspicuous successes — on immigration, say, or economic policy — to which they can point.

Despite hard-right election gains in Germany, the Netherlands, Poland, and Austria, Professor Ansell said, there is a chance that Europe may have passed its moment of “peak populism.” In Austria, the far-right Freedom Party was locked out of government despite winning the most votes, after three mainstream parties stitched together an alternative coalition.

In Germany, the hard-right Alternative for Germany, or AfD, emerged as second-largest party in elections last month, trailing only the Christian Democrats, which are led by Friedrich Merz, the presumptive chancellor. But some analysts had expected the party to perform even better than it did, given that Mr. Musk and Vice President JD Vance endorsed it.

“It’s still bad enough that 20 percent of the people voted for an anti-system, pro-Russia party,” said Ms. Stelzenmüller of the Brookings Institution, “but it’s clear the AfD didn’t gain from Musk’s and Vance’s efforts to campaign on its behalf.”

Nor has the AfD been a central player since the election, as Mr. Merz tries to engineer a landmark relaxation of Germany’s debt laws to enable it to fund a mammoth increase in military spending. Mr. Merz has staked a claim to leadership with his call for Europe to take charge of its own security because of the threat posed by Russia and the unreliability of the United States.

To be sure, Mr. Merz is scrambling to act now because he would have more trouble getting such an increase through the next Parliament, in which the AfD, which opposes the spending, would have enough votes to block it.

It is not clear that Mr. Merz has the votes to pass the measures, which will also need significant support from the Green Party to clear a two-thirds hurdle in Parliament. Privately, Mr. Merz’s aides contend that Mr. Trump has given the would-be chancellor the only argument he needs to prevail. He is the first American president to so explicitly threaten to pull American support.

In Britain as in Germany, analysts said the political landscape could shift again. Mr. Starmer’s pledge to increase military spending, they said, will force the Labour Party into painful trade-offs on taxes and spending that are already exposing rifts within the party. And Mr. Starmer’s recent success on the world stage could prove fleeting if he cannot turn around the economy and rebuild public services.

In that sense, Mr. Starmer’s up-and-down government has something in common with Mr. Trump’s, even if the president’s chaotic debut has so far played to the advantage of the prime minister and other centrists.

“The shine, such as it was, of Trump’s first few weeks has emphatically worn off, and in both foreign policy and economic outcomes, the picture has turned very dark,” Professor Ansell said.

Jim Tankersley contributed reporting from Berlin

Italian employees at the Aviano Air Base in northern Italy paused from flipping burgers, unloading trucks and restocking shelves recently to open an email from their bosses demanding that they list five key accomplishments from last week.

The email was a by-now familiar demand from President Trump’s chief cost-cutter, Elon Musk, carrying with it the threat of termination if they did not respond. But on this occasion, it did not land with government employees in the United States, but rather in Italy, a country where workers’ rights are held sacrosanct.

The result set the stage for a puzzling clash of cultures, with the world’s richest man and his job-thrashing chain saw on one side, and one of the world’s most protective champions of the forever job on the other.

“We are in Italy here,” said Roberto Del Savio, a union representative and an employee at the base. “There are precise rules and thank God for that.”

Aviano, an Italian air base that hosts the United States 31st Fighter Wing, employs more than 700 Italian civilian personnel who on a daily basis cook and clean and generally keep the base running.

In all about 4,000 Italian civilian employees work at bases serving about 15,000 American soldiers in Italy, turning each into a sort of a miniature American town where U.S. military personnel can find American food and other familiar items from home.

Those jobs, in keeping with longstanding labor traditions in Italy, are fully unionized and protected under Italian labor laws. But at the same time, the employees work for the United States government, which pays their salaries.

Labor unions say the email was forwarded from a department head to dozens of Italian civilian employees working in the Aviano base’s Army & Air Force exchange service, which provides goods and services to the U.S. Army.

No one seemed certain whether it was a one-off misunderstanding or if Mr. Musk was attempting to assert his demands over Italian workers as well as American ones. A Department of Defense official said that while those emails were meant for U.S. employees, local employees “could receive emails,” too.

The confusion raised questions of whether Mr. Musk could export his brand of unbridled techno-libertarianism to a country that is “founded on labor” per the first article of its Constitution, or whether his chain-saw would snag on Italy’s notoriously thick bureaucracy.

“Ours is a system built on democracy, safeguards, and protections provided by contracts that must be respected,” Pierpaolo Bombardieri, the secretary general of Italy’s Uil union said in a statement.

Mr. Bombardieri called the emails “unacceptable” and the method “aberrant.” Italy’s unions wrote to the Italian government and the U.S. Embassy asking for explanations.

For now, the ground rule appears to be that Italian civilians must answer the email only if they receive it directly from the U.S. government — not if it is forwarded to them, as happened at Aviano and at least one other base in Italy, in the city of Vicenza. But it remained unclear whether the Department of Defense was going to reach out to Italian workers directly.

Some German employees of the U.S. government in Germany also received Mr. Musk’s first email asking them to explain their work output, said a senior diplomat in Berlin, who did not want to be named while talking about an ally. (Mr. Musk’s follow-up email appears to have been sent only to American employees in Germany, the diplomat said.)

In the meantime, some Italian employees had answered the email, said Mr. Del Savio. “One says I was slicing pizza, another says something else.” he said. “But we were all very puzzled,” he said. “Italy is not the Wild West like the U.S.”

Despite recent changes that attempted to make the labor market more flexible, Italy’s labor laws continue to offer broad protections to employees. Especially in the public sector, getting a permanent job is often seen as a guarantee to be unfireable for life.

Many in Italy value this system as a backbone of the Italian welfare state and its democracy, while others point to it as a rigid and inefficient juggernaut that prevents jobs from being created for young people.

Stories of half-hour long workdays and daylong coffee breaks are something of a legend in Italy. Some have said a touch of Musk-style slash and burn approach would not hurt here.

“Italy would also need Musk’s ax,” Nicola Porro, an Italian journalist and right-wing commentator, wrote in a blog post, decrying Italy’s “useless positions.”

Italians seized upon the juxtaposition. One TikTok creator, Alberico Di Pasquale, made a video pretending to show an Italian employee on a permanent contract answering Mr. Musk’s email. “No. 1: I come to work, No. 2: I clock in, No. 3: breakfast,” he said. “No. 4: tournament with my colleagues to see who will get the coffee; No. 5: I get the coffee. Repeat five times points 4 and 5. No. 6: I go pay my bills and grocery shop; No. 7, I clock out.”

But while some had fun with the demands from Mr. Musk, for union representatives at the American base in Aviano, and other Italians, it was serious business.

As Mr. Trump questions the U.S. commitment to NATO and insists that Europe must defend itself, fears of spending cuts are spreading at U.S. bases abroad.

Amid a 30-day freeze of federal credit cards, the U.S. government last week also froze the credit cards that Italian employees at Aviano used to purchase equipment for the base, then started a hiring freeze, the unions said.

Union workers said they did not know what was going to come next. But they said they were going to fight on.

“Musk can do whatever he wants in the United States,” said Emilio Fargnoli, a union representative. “If they are happy with it, sure,” he added. “Not here.”

Jim Tankersley and Jeanna Smialek contributed reporting.

With Greenland thrust into the spotlight by President Trump’s insistence that the United States will somehow “get” it, Greenlanders held a closely watched election on Tuesday that took on unusual importance — not just for the outside world, but for them as well.

Voter turnout hit its highest level in more than a decade, and polling stations on the remote, sparsely populated island, which is partly controlled by Denmark, stayed open late to accommodate long lines.

But with all votes counted early Wednesday morning, the results were mixed.

The winner was Demokraatit, a party that has been critical of Mr. Trump’s rhetoric. It has taken a moderate stance on the subject of independence from Denmark, which most Greenland politicians support as a long-term goal.

The second most popular party, Naleraq, however, has pushed hard for independence as soon as possible — which some of its members have said would enable Greenland to associate more freely with other countries, including the United States. One of Naleraq’s most prominent figures is very pro-Trump and attended the American president’s inauguration.

Greenlanders are clearly divided, experts said, on how to handle this crossroads.

“What has become clear during the election — and what Denmark must now recognize — is that across the political spectrum, there is dissatisfaction with the current constitutional arrangement,” said Ulrik Pram Gad, a researcher at the Danish Institute for International Studies in Copenhagen. “Regardless of the outcome, there will be calls for renegotiating the structure of the kingdom of Denmark.”

Denmark colonized Greenland more than 300 years ago, and while the island is now considered a semiautonomous territory, Denmark still controls foreign policy, defense and other aspects of its governance. Demokraatit — which won just under 30 percent of the vote, ahead of Naleraq’s 24.5 percent — has consistently argued that independence must not imperil economic and social stability. There are only 56,000 people living on the island, and the difference between first and second place in this election was around 1,500 votes.

Lars Trier Mogensen, a political analyst based in Copenhagen, said he did not expect any drastic changes in Greenland’s geopolitical situation, at least for now.

“The new Greenlandic government is unlikely to rush into major shifts in U.S. relations anytime soon,” he said.

In interviews with voters these past few weeks and during town hall events with candidates, it was local issues like health care, schools and fishing (the island’s main industry) that kept coming up. Some observers said the two leading parties were clearer about what needs to be changed.

For example, they both campaigned on revamping the fisheries law, said Svend Hardenberg, a mining executive and, more recently, a star in a popular Danish Netflix series that, serendipitously, had a whole season about Greenland.

“The main direction is independence,” he said. “I think that can go quicker than most people expect.”

Greenland boasts a trove of minerals and is strategically located near increasingly important Arctic Ocean shipping lanes. Mr. Trump, in an address to Congress last week, said, “I think we’re going to get it — one way or the other, we’re going to get it.”

On Sunday, two days before the election, in a social media post, he made a direct pitch to Greenlanders: “We are ready to INVEST BILLIONS OF DOLLARS to create new jobs and MAKE YOU RICH.”

But Greenlanders have been clear that despite Mr. Trump’s entreaties, they don’t want to be absorbed by the United States, with polls showing that at least 85 percent oppose the idea. “Greenland is not a house that can be bought,” Demokraatit’s leader, Jens-Frederik Nielsen, has said.

Still, Kuno Fencker of Naleraq, who is Greenland’s most pro-Trump politician, got far more votes than he did in the last election, in 2021. Mr. Fencker attended Mr. Trump’s inauguration and took a tour of the West Wing, and his push for stronger ties with the United States drew fierce criticism from his rivals, some of whom labeled him a traitor. In a recent podcast, Mr. Fencker argued that Mr. Trump had been “misunderstood.”

Naleraq’s second-place finish means that pro-independence voices will remain influential, and the party could push for greater engagement with Washington. But Mr. Fencker’s enthusiasm for Mr. Trump might have turned off some voters, analysts said.

“Naleraq positioned itself in a way that made it seem like a vote for them would bring Trump too close,” Mr. Gad said.

Naleraq doubled its seats, from four to eight, in Greenland’s 31-seat Parliament, the Inatsisartut. At an election night party on the outskirts of Nuuk, the capital, party members and supporters embraced, danced and cheered.

Analysts predicted that Demokraatit was likely to form a governing coalition with the more moderate Inuit Ataqatigiit party, or I.A., which finished third, with 21.4 percent of the vote. Inuit Ataqatigiit, the dominant party in the outgoing governing coalition, embraced a go-slow approach to breaking off from Denmark.

Greenland, the world’s biggest island, is home to a mostly Inuit population that Denmark sidelined during the colonial era. Over time, demands for self-rule have led to greater autonomy and a Greenlandic government. One of Naleraq’s selling points, Mr. Gad said, was its “activist language” inspired by international movements like #MeToo and Black Lives Matter.

Today, Greenland manages most of its domestic affairs. But full independence is not going to be easy. Denmark sends hundreds of millions of dollars to the island each year that pays for nice schools, cheap gas and strong social services — a Scandinavian standard of living in a very remote place. Many Greenlanders, even if they are leaning toward independence, have said they are reluctant to jettison all that, which is why the subject of breaking off from Denmark is so sensitive.

Many voters also expressed skepticism, worry and even anger about the way Mr. Trump has talked about their homeland. People have been living on this icy island for thousands of years, surviving off hunting and fishing. The sense of Greenlandic identity runs strong, and during the election, ballots had to be transported by helicopter, boat and snowmobile.

In the final televised debate on Monday, five of the six party leaders said they did not trust Mr. Trump. Only Karl Ingemann of the small Qulleq party said he did. And Mr. Ingemann failed to win a seat.

The arrest warrant was delivered to President Ferdinand R. Marcos Jr. of the Philippines in Manila at 3 a.m. Monday. The person named on it: his predecessor, Rodrigo Duterte, the firebrand whose war on drugs left thousands of people dead.

But acting on the warrant from the International Criminal Court was not straightforward, since the Philippines is not a member of the court. So at 6:30 a.m., Mr. Marcos’s government received another warrant for Mr. Duterte, this time from Interpol, which was acting on the court’s behalf and of which the Philippines is a member.

Mr. Marcos recalled his next step in an address to the nation on Tuesday. “OK, we’ll put all our plans into place, and let’s proceed as we had discussed,” he relayed having told the head of his justice department.

Just over 24 hours later, Mr. Duterte — who long seemed above the law — was arrested in Manila. By the end of Tuesday, he had been put on a plane bound for The Hague to face charges of crimes against humanity.

It was a swift coda to a long chapter of impunity in the Philippines. Only a handful of people have been convicted in connection with the killings in Mr. Duterte’s drug war, in which as many as 30,000 are estimated to have died. Now, the man who publicly took credit for the carnage was being sent to a court of law to face justice, in part because of a shift in political winds.

Mr. Marcos, the son of the dictator Ferdinand E. Marcos, rose to power after forming an alliance with Sara Duterte, a daughter of Mr. Duterte’s. Running on a platform of national unity, they won the presidency and vice presidency in 2022. But their marriage of convenience started unraveling quickly, driven by mistrust.

Ms. Duterte, who is leading in the polls to succeed Mr. Marcos, has railed against him, saying that she wanted to cut his head off and threatening to dig up his father’s body and throw it into the ocean. Her own father called the younger Mr. Marcos a “drug addict” and a “weak leader.”

Mr. Marcos mostly brushed off the comments and said little in public. But his allies impeached Ms. Duterte last month, imperiling her political career.

Then came the arrest of her father, which she and her allies denounced as political oppression, although Mr. Marcos said he had simply been following international convention in complying with the Interpol warrant.

“This was justice, regardless of how we got here,” said Maria Ressa, the Nobel Prize-winning journalist who has long been a target of Mr. Duterte because her news website, Rappler, has investigated the drug war.

“Now, is there politics involved? There is always politics involved,” she added. “But it’s a reminder to the rest of the world that accountability comes for you sooner or later and that impunity doesn’t last forever.”

It was still hard for some Filipinos to believe that such a moment had arrived.

Florecita Perez and Joemarie Claverio’s son, Jenel Claverio, 27, was killed by masked men in Navotas in December 2019. This week, Ms. Perez said in an interview, she pumped her fist in the air when she heard about Mr. Duterte’s arrest, but waited until nighttime to tell her partner, because she thought the news would make him cry.

As they were about to sleep, she hugged him from behind. “I said, ‘Hon, Duterte has been arrested.’ He turned to me and said, ‘Oh? Won’t he be able to get away?’”

Mr. Duterte landed in the Netherlands on Wednesday evening, and he was to be taken to The Hague, where both the I.C.C. and its detention facilities are based. A court official said that Mr. Duterte would not be expected to appear in court on Wednesday, but he would likely be arraigned before a three-judge panel in the next few days.

The I.C.C. typically has lengthy pretrial proceedings, and a planned trial is not expected to start for months.

Ms. Duterte was also on her way to The Hague, to help organize her father’s legal team. Another daughter of the former leader’s, Veronica Duterte, posted screen grabs of video calls with their father while he was on the plane. In one Instagram post, she wrote: “A flight lasting more than eight hours but left with just a sandwich to eat???”

But thousands of people rejoiced when the chartered flight carrying Mr. Duterte took off from an air base in Manila. To some, it was reminiscent of when Mr. Marcos’s father was ousted nearly four decades ago and fled to the United States.

“It’s not quite what it must have been like for my parents on Feb. 25 with those headlines in the newspaper, saying: ‘It’s all over, Marcos leaves,’ but it felt pretty close,” said Sol Iglesias, an assistant professor of political science at the University of the Philippines. (Critics accuse the younger Mr. Marcos of trying to whitewash history by not properly recognizing the significance of that day in 1986.)

Ms. Iglesias said it was clear that the current president had given clearance for the broad campaign to curtail the Dutertes’ power in recent months.

“None of these would have been possible without his assent,” she said.

Despite having once pledged not to cooperate with the I.C.C., Mr. Marcos told reporters in November that he would not block the court and that it had obligations with Interpol.

Mr. Duterte left office with one of the highest approval ratings in Philippine history, and Ms. Duterte is still leading polls for the presidency in 2028, but the arrest now leaves her in a highly vulnerable position. And in recent months, the Dutertes have not been able to galvanize large crowds for their protests.

In approving Mr. Duterte’s arrest, Mr. Marcos is gambling that he can eliminate the Dutertes as a political force without any major backlash. The issue is now likely to be front and center during the midterm elections, seen as a proxy battle between the Marcoses and the Dutertes, in May.

Two Duterte allies — his former aide, Christopher “Bong” Go; and a former police chief, Ronald “Bato” Dela Rosa, the architect of Mr. Duterte’s drug war — are seeking re-election to the Senate. Later this year, Philippine senators will decide whether to convict Ms. Duterte over her impeachment. A ruling against her would all but put her out of the running for the top job.

So far, public sentiment seems to be behind Mr. Marcos. A March 2024 survey of more than 1,700 Filipinos showed that nearly three in five approved of the I.C.C. investigation.

On Wednesday night, in the city of Cotobato, a stronghold of Mr. Duterte, residents held banners and lit-up cellphones in protest of his arrest. A few hundred people turned up, but the demonstration soon petered out.

Marlise Simons contributed reporting from Paris, and Aie Balagtas See and Camille Elemia from Manila.

Europeans reacted with relief to the announcement on Tuesday that Ukraine had agreed with the United States on a 30-day cease-fire in its war with Russia and anxiously awaited Moscow’s response.

They were relieved because Washington announced simultaneously that it would immediately restore military and intelligence support for Ukraine. And there was expectation that Russia must now respond in kind, or presumably President Trump would put some kind of pressure on Moscow analogous at least to the blunt instruments he used against Ukraine.

“The ball is now in Russia’s court,” said the two European Union leaders, António Costa and Ursula von der Leyen, in coordinated messages on social media welcoming the deal and echoing the statement of Secretary of State Marco Rubio.

But in the same sentence the European leaders also welcomed the resumption of U.S. security support to Ukraine, giving it equal emphasis.

“We welcome today’s news from Jeddah on the U.S.-Ukraine talks, including the proposal for a cease-fire agreement and the resumption of U.S. intelligence sharing and security assistance,” the message said on Tuesday. “This is a positive development that can be a step toward a comprehensive, just and lasting peace for Ukraine.”

They also tried to remind Mr. Trump and his team that if Washington wants Europe to guarantee any peace deal in Ukraine, Europe wants to be at the negotiating table. “The European Union,” the message said (hint, hint), “is ready to play its full part, together with its partners, in the upcoming peace negotiations.”

In general, European leaders were shocked by the anger displayed against President Volodymyr Zelensky of Ukraine in the infamous Oval Office news media gaggle on Feb. 28 and Mr. Trump’s apparent acceptance of the Russian narrative that Ukraine started the war.

They were also struck when Mr. Trump’s special envoy, Keith Kellogg, said that Ukraine had to be hit in the head, “sort of like hitting a mule with a two-by-four across the nose,” to get it to comply with Mr. Trump’s demands. The lumber turned out to be the denial of lifesaving American military and intelligence support to Ukraine, its missiles and its American-built fighter jets.

That prompted some in Europe, like Nathalie Tocci, director of Italy’s Institute of International Affairs, to wonder if Washington would do the same to them some day, and whether it was such a good idea to buy so much high-tech American weaponry, like F-35 fighter jets, that depends on American software and integration with American satellites.

European leaders gathered in Paris, London and Brussels last week and this one to promise Ukraine continued and even increased support. “Ukraine is a matter of our own security,” said Norbert Röttgen, a foreign policy expert and German member of Parliament for the Christian Democrats. “If Ukraine falls, it would be a clear threat to Europe.”

But the key point, emphasized by President Emmanuel Macron of France and Prime Minister Keir Starmer of Britain, was that Ukraine needed American backing. Europe, despite all its vows to continue providing Ukraine with money and weapons, cannot replace key American capabilities like intelligence and missile defense, at least not in the near future.

So European leaders were also relieved at Mr. Zelensky’s understanding of his quandary. After the Oval Office blowup, they worked hard to persuade Mr. Zelensky to kowtow to the White House with repeated expressions of gratitude to assuage Mr. Trump. Mr. Zelensky did so, while promising that he continued to support another demand of Mr. Trump for providing the United States privileged access to Ukraine’s mineral wealth, and a share of it besides.

The Europeans have been urging Mr. Zelensky to go along for now to put pressure on Russia and help Mr. Trump see that its president, Vladimir V. Putin, is the problem.

Defense ministers from Europe’s most significant military powers — France, Italy, Germany, Poland and Britain — met in Paris on Wednesday, a day after a gathering of military chiefs from over 30 countries in the French capital to discuss security guarantees for Ukraine, including the potential formation of a multinational peacekeeping force to monitor any cease-fire.

But the defense ministers gave no concrete details about the potential size or mission of a peacekeeping force, calling such discussions premature at a time when fighting was still raging between Russia and Ukraine.

“We mustn’t put the cart before the horse,” said Sébastien Lecornu, France’s defense minister, who like his counterparts added that “the first security guarantee for Ukraine is the Ukrainian Army itself.”

“You aren’t going to ask European troops to do the Ukrainian Army’s job,” he later added.

The Europeans have also gathered to have preliminary discussions of what they might be prepared to do to guarantee a future longer-term deal between Ukraine and Russia. Much remains unknown, including the purpose of such a force, its size, financing and command structure. But the Europeans do know they will need American cooperation and air support to make such a mission credible.

Nor is it even clear that Moscow will relent on its current refusal to consider allowing European troops in Ukraine, given that one of the main aims of Russia’s invasion was to keep Ukraine from joining NATO and allowing NATO troops to base there.

But Mr. Macron in particular has gone further, seeing the American turnabout on Ukraine as yet another sign that Europe must do more for its own defense and not rely so much on a United States that appears indifferent to Europe, if not openly hostile to it, both economically and politically.

Now Europeans, like Ukrainians, wait for the response of Mr. Putin. So far, he and his officials have rejected the idea of a cease-fire before a final settlement of the conflict. And there are no guarantees that even if a 30-day cease-fire were put in place the war would not recommence, giving at least some the impression that Mr. Trump simply wanted a victory to show that he could stop the killing, even temporarily.

Aurelien Breeden contributed reporting from Paris.

As recently as January, President Vladimir V. Putin of Russia emphatically rejected the idea of a temporary cease-fire in Ukraine.

But after a month in which President Trump turned American foreign policy on its head and Russian forces made progress in a key battle, the Kremlin now appears keen at least to entertain the 30-day cease-fire proposal made by Ukraine and the United States on Tuesday.

Dmitri S. Peskov, Mr. Putin’s spokesman, told reporters on Wednesday that the Kremlin was “carefully studying” the outcome of Tuesday’s talks between the United States and Ukraine, and their call for a monthlong cease-fire.

He said he expected the United States to inform Russia in the coming days of “the details of the negotiations that took place and the understandings that were reached.” He raised the possibility of another phone call between Mr. Putin and Mr. Trump, signaling that the Kremlin saw the cease-fire proposal as just a part of a broader flurry of diplomacy.

Late Wednesday, Mr. Putin sought to show he was in control of events by donning military fatigues and holding a televised meeting with his top military officials charged with pushing Ukraine out of Russia’s Kursk region, where Russia has made progress in recent weeks. He directed his troops to defeat Ukraine in the region “in the shortest possible time,” a move that, if successful, would deny Ukraine a key point of leverage in any negotiations with Russia.

Mr. Putin has seen a dizzying reversal in his geopolitical fortunes over the last month as Mr. Trump realigned American foreign policy in Russia’s favor, antagonized U.S. allies and excoriated President Volodymyr Zelensky of Ukraine at the White House.

But the emergence of a joint cease-fire proposal from the United States and Ukraine complicates things for Mr. Putin. It deepens the tension between his desires for a far-reaching victory in Ukraine and for close ties with Mr. Trump.

While Mr. Trump says he wants to end the war as soon as possible, Mr. Putin has signaled he will not stop fighting until he extracts major concessions from the West and from Kyiv, including a pledge that Ukraine will not join NATO and that the alliance will reduce its presence in Central and Eastern Europe.

On Jan. 20, when he congratulated Mr. Trump on his inauguration, Mr. Putin made clear that the goal of any Ukraine talks must “not be a short cease-fire, not some kind of respite.” Russia, he said, sought “a long-term peace based on respect for the legitimate interests of all people, all nations who live in this region.”

Analysts say Mr. Putin’s opposition to a temporary cease-fire stemmed from the simple calculation that with Russian forces gaining on the battlefield, Moscow would only give up its leverage by stopping the fighting without winning concessions.

But a Feb. 12 phone call between Mr. Putin and Mr. Trump, and the White House’s subsequent alignment with Russia at the United Nations and elsewhere, may have affected Mr. Putin’s calculus by making him more eager to stay on Mr. Trump’s good side, analysts say.

That sets up a delicate balancing act for the Kremlin.

Ilya Grashchenkov, a political analyst in Moscow, said the Kremlin could be tempted to accept a truce that would be “tactically unfavorable but strategically favorable” in order to “show that it’s a peacemaker.”

While Russians were not present at Tuesday’s talks in Jeddah, Saudi Arabia, the Trump administration has kept up its engagement with the Kremlin. John Ratcliffe, the C.I.A. director, spoke to his Russian counterpart, Sergei Naryshkin, on Tuesday, Russia’s foreign intelligence agency said on Wednesday.

Steve Witkoff, the envoy for Mr. Trump who met with Mr. Putin for several hours last month, plans to return to Russia in the coming days, according to two people familiar with the matter, who requested anonymity to discuss internal plans. Mr. Trump on Tuesday said that he thought he would speak with Mr. Putin this week, and he told reporters at the White House on Wednesday that his negotiators were en route.

“People are going to Russia right now as we speak,” Mr. Trump said during a meeting with Ireland’s prime minister. “And hopefully we can get a cease-fire from Russia.”

In a sign of Moscow’s continuing charm offensive directed at the Trump camp, Russia’s foreign ministry released a 90-minute interview on Wednesday that the foreign minister, Sergey V. Lavrov, gave to three American video bloggers, including the former Fox News personality Andrew Napolitano.

Mr. Lavrov, speaking English, praised the Trump administration for reversing the Democrats’ “departure from Christian values” and said Russia was ready for the “normal relations” that the United States was offering.

“It certainly is not impossible that the Russians would accept this,” Samuel Charap, a Russia analyst at the RAND Corporation, said of the 30-day offer. “Not because they want an unconditional, temporary cease-fire, but because they now have a stake in relations with Washington.”

Mr. Putin’s calculus could also be affected by Russia’s progress in recent days in pushing Ukrainian troops out of Kursk, the Russian border region where Ukraine occupied several hundred square miles of territory in a surprise incursion last August.

Mr. Zelensky had said he planned to use that land as a bargaining chip in future talks, but the Kremlin signaled that it would refuse to negotiate so long as Ukraine held the territory.

With the Kursk region mostly back in Russian hands, Mr. Putin no longer risks losing face by agreeing to a cease-fire that would leave Ukraine in control of an area of Russian territory, said Sergei Markov, a pro-Kremlin political analyst in Moscow.

A further incentive to agree, Mr. Markov said, was to make sure that Russia “doesn’t look like a war maniac” in the eyes of non-Western countries that have avoided imposing sanctions on Moscow. But, he said, he expected Mr. Putin to insist on preconditions, such as a halt on weapons supplies to Ukraine for the duration of the cease-fire.

“Russia will very likely say, ‘Yes, but —,’” Mr. Markov said in a phone interview.

Russia’s popular pro-war bloggers on Wednesday did not display much enthusiasm for a cease-fire. Some of them expressed concern that a truce could eventually lead to a broader deal with the United States that, in their view, would betray the original goals of the war and eventually lead to a Russian withdrawal from Ukraine.

One blogger, who goes by the name Alex Parker Returns, argued in a post on Wednesday that a peace deal would allow Ukraine “to get off easily and get ready for the next round.”

Ivan Nechepurenko contributed reporting.