The tutelage began last Friday, soon after President Volodymyr Zelensky of Ukraine suffered through a humiliating dressing down at the White House, courtesy of President Trump.

Prime Minister Keir Starmer of Britain suggested that Mr. Zelensky return to the White House to mend fences with Mr. Trump. That idea was scotched by both sides, who concluded it would be better to let tempers cool, according to a British official familiar with the discussion.

But it was the beginning of five days of prodding and counseling from Mr. Starmer and French President Emmanuel Macron, who both told Mr. Zelensky that he needed to change his approach to Mr. Trump, according to the British official and French officials close to Mr. Macron. They spoke on condition of anonymity because of the sensitivity of the matter.

The conversations took on greater urgency after the White House announced on Monday that it would halt American aid to Ukraine.

After talking to both leaders on Tuesday, Mr. Zelensky made a significant course correction, one taken by many world leaders when trying to win over Mr. Trump: He offered effusive praise and gratitude, gushing over the assistance America has provided to Ukraine’s war effort.

He also sought to assuage the American president’s unsupported claims that Mr. Zelensky did not want peace, going so far as to outline specific steps that could be taken on a path toward a settlement — like a cessation of missile strikes. Ukraine was “ready to work under President Trump’s strong leadership to get a peace that lasts,” Mr. Zelensky wrote on X.

“I think that Zelensky has realized that he needs to change his tactics with regard to Trump in accordance with Trump’s worldview,” said Oleksandr Merezhko, the chairman of the Foreign Affairs Committee in Ukraine’s Parliament. “In Machiavellian terms, if you are not a lion in politics, like Trump, you have to be a fox,” he said.

That was something other world leaders have taken to heart and that Mr. Zelensky has struggled to adjust to.

“To get Trump’s support you need to behave as if you are under his protection and he is the Godfather whom you admire and look up to,” Mr. Merezhko said in an interview. “Trump doesn’t stand those who try to behave as if they are equal to him.”

Speaking to Congress on Tuesday night, Mr. Trump seemed to beam as he described Mr. Zelensky’s outreach, and his expressions of gratitude. He said that he received a letter from Mr. Zelensky in which the Ukrainian leader wrote that he was serious about a peace settlement.

Mr. Zelensky went out of his way to single out Mr. Trump for praise.

“We remember the moment when things changed when President Trump provided Ukraine with Javelins,” he wrote on X, alluding to the missiles the U.S. provided to Ukraine early in the war. “We are grateful for this.”

It is no secret that flattery is a pathway to Mr. Trump’s good graces.

But it remains to be seen how successful the strategy will be even for leaders Mr. Trump appears to get along with, like Mr. Macron.

History suggests many of those efforts will fail.

By the end of his first term, Mr. Trump had soured on several leaders with whom he started off on good terms, including Prime Minister Justin Trudeau of Canada. Clashes over his trade policies and aversion to alliances overrode any rapport that the leaders tried to cultivate.

His disdain for Mr. Zelensky was evident in the tone of the Oval Office dressing down he and Vice President JD Vance gave the Ukrainian leader.

Mr. Trump is surrounded by people, including his son, Donald Trump Jr., and Elon Musk, who routinely express deep, almost personal, loathing for Mr. Zelensky openly. At the same time, they put forth Kremlin talking points.

Mr. Zelensky’s statements are dissected by Mr. Trump and his allies and portrayed as somehow critical of Mr. Trump. The response is then amplified on Mr. Musk’s social media platform, X, and the echo chamber of media outlets aligned with the president.

The latest snippet of a quote that stoked Mr. Trump’s fury was Mr. Zelensky’s suggestion that a lasting peace deal was a long way away. Mr. Trump appeared to take it as an affront to his efforts to get a quick settlement, and used it to assail the Ukrainian leader as not being serious about peace.

Some analysts have said that, given the power imbalance between the two leaders, it is better to accept that Mr. Trump has his own version of events and act accordingly.

Before Mr. Trump’s election, Mr. Zelensky was well aware how quickly the political pendulum can swing in Washington, so his team carefully sought to cultivate bipartisan support in Washington.

In at least 94 statements of gratitude to the American people over the past three years — compiled in a video montage released by the United24, the Ukrainian state charity — he often made a point of thanking both Democrats and Republicans.

Ukraine’s leaders are determined to not let themselves be painted as ungrateful.

The Ukrainian Air Force released a video on Wednesday featuring a pilot, Vadym Voroshylov, thanking America for helping in its fight for freedom. “Thank you for your support. Together to victory,” he wrote.

After Mr. Trump’s election, Mr. Zelensky repeatedly flattered the new American president, saying he agreed with an approach that featured “peace through strength” and said time and again that Mr. Trump was the only one with the strength to force President Vladimir V. Putin of Russia to the negotiating table.

Aware of Mr. Trump’s well-documented transactional approach to foreign policy, Mr. Zelensky was the one who first suggested that helping defend Ukraine could be in America’s economic interests since his country “is rich in natural resources, including critical metals worth trillions of U.S. dollars.”

But many in Ukraine, as well as in Europe, have come to the conclusion over the last two weeks that Mr. Trump is determined to align himself with Moscow, no matter the cost to Ukraine or Europe.

“If we know he is under Russian influence, do we have a chance to break this influence?” asked Vadym Prystaiko, a former Ukrainian foreign minister and ex-ambassador to the United Kingdom, in an interview with Ukrainian media.

“So how do we do it? What methods do we use — culture, art, personal connections, public messaging, and so on? If we fail, what’s our second option? We act knowing that this is what he thinks.”

In his statement praising Mr. Trump and pledging to work with him to end the war, Mr. Zelensky sought to test the notion that Russia was ready for peace, offering to immediately initiate a partial truce in the air and sea provided Russia did the same.

While Mr. Trump told Congress that Mr. Putin had sent “strong signals” that he is ready for peace, he made no mention of the Ukrainian truce proposal.

The American alignment with Moscow has led many inside and outside Ukraine to speculate that Mr. Trump believes the quickest way to end the war is to force Kyiv to essentially surrender.