Sources told Politico that one of the reasons Trump became more sympathetic to Ukraine was his joint summit with Russian President Vladimir Putin in Alaska.

Politiko reminds that Trump warmly greeted Putin in Alaska and that the Russian leader was welcomed there as a friend.

Putin left Anchorage without agreeing to a truce, despite Trump saying during their joint press conference that the Russian leader was trying to save thousands of lives.

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A Republican foreign policy insider said that after the meeting in Alaska, Putin showed no concern for human life and that the continued attacks on civilian targets in Ukraine had a major impact on Trump's change of heart.

"Trump needed time to understand who Putin really is," the source said.

The insider added that Trump was furious at the media coverage of the summit, which was described as"Putin's triumph".

Europe is trying to reduce tensions

Meanwhile, European leaders close to Trump tried to ease tensions between the US president and his Ukrainian counterpart Volodymyr Zelensky after their on-camera spat in the Oval Office.

A Republican insider named key figures in this process as British Prime Minister Keir Starmer, Finnish President Alexander Stubb, NATO Secretary General Mark Rutte and Starmer's national security adviser Jonathan Powell.

The source also said that Britain's King Charles played a decisive role"telling Trump that Ukraine is great and that really changed Trump's view of Ukraine."

The insider also thanked Zelenskyi for working diligently on his relationship with Trump and being careful in his later statements.

"You have to understand that since the beginning of the war Zelensky and [Andrii] Yermak [Chief of Cabinet of the President of Ukraine] are used to being treated like rock stars, like world celebrities, and then Trump comes in and says: 'there's only room for one diva here - me'. That's why we had an explosion in the Oval Office."

Evidence of improving relations includes increasingly friendly meetings between Trump and Zelensky, the warmest of which took place on the sidelines of the UN General Assembly last month, when Trump praised the Ukrainian leader as a"brave man."

Among other factors shaping Trump's changing view of Ukraine, another Republican foreign policy adviser cited China's reception of Putin and North Korean leader Kim Jong Un last month.

"The best way to take revenge on Putin is to praise Zelensky - that's how Trump sees it," said the adviser.

To that end, Washington recently increased intelligence sharing with Ukraine's defense forces to help attack energy facilities deep in Russia.