US President Donald Trump and Ukrainian President Volodymyr Zelensky have agreed to work together to end Russia’s war with Ukraine, in what the White House described as a “fantastic” one-hour phone call.

On Thursday (AEDT), the Trump administration said that he had suggested the US could help run, and possibly own, Ukraine’s nuclear power plants.

Europe’s largest nuclear power plant, in Ukraine’s Zaporizhzhia region, has been shut down since Russian troops occupied it in 2022.

Later on Thursday, Zelensky said Ukraine had begun talks with the US about its possible involvement in restoring the Zaporizhzhia plant.

In their first conversation since an Oval Office shouting match on February 28, Zelensky thanked Trump for US support and the two leaders agreed that technical teams would meet in Saudi Arabia in the coming days.

Zelenskiy asked Trump for more air defence support to protect his country against Russian attacks, while Trump said he would help get the necessary military equipment to Europe, the White House said.

Trump briefed Zelensky on his phone call on Tuesday with Vladimir Putin.

Putin has rejected a proposed full 30-day ceasefire sought by Trump and accepted by Ukraine, but did agree to pause attacks on energy infrastructure.

That narrowly defined pause appeared in doubt on Wednesday, however, with Moscow saying Ukraine hit an oil depot in southern Russia while Kyiv said Russia had struck hospitals and homes, and knocked out power to some railways.

Still, the two sides carried out a prisoner exchange, each releasing 175 troops in a deal facilitated by the United Arab Emirates. Moscow said it freed an additional 22 wounded Ukrainians as a goodwill gesture.

Zelensky, describing his conversation with Trump as “positive, very substantive and frank”, said he had confirmed Kyiv’s readiness to halt strikes on Russian infrastructure and its commitment to an unconditional frontline ceasefire as the US proposed earlier.

“One of the first steps toward fully ending the war could be ending strikes on energy and other civilian infrastructure. I supported this step, and Ukraine confirmed that we are ready to implement it,” he said on social media.

Later, he told journalists in a media call that Trump understood that Kyiv would not recognise occupied land as Russian.

Zelensky said the Russian strikes, which he said came after Trump’s call with Putin, showed that Russia was not ready for peace. He said the US should be in charge of monitoring any ceasefire, adding a halt to infrastructure attacks could be quickly established.

Later Secretary of State Marco Rubio said Trump and Zelensky had discussed “Ukraine’s electrical supply and nuclear power plants” with Trump saying “the United States could be very helpful in running those plants with its electricity and utility expertise”.

“American ownership of those plants would be the best protection for that infrastructure and support for Ukrainian energy infrastructure,” Rubio said.

Zelensky said only the Zaporizhzhia facility was discussed.

Trump has long promised to end Europe’s deadliest conflict since World War II. But his outreach to Putin has unnerved European allies, who fear it heralds a fundamental shift after 80 years in which defending Europe from Russian expansionism was the core mission of US foreign policy.

Some European leaders said Putin’s rejection of Trump’s proposed full truce was proof Moscow was not seeking peace. The offer to temporarily stop attacking Ukrainian energy facilities counted for “nothing” and Trump would have to win greater concessions, Germany’s defence minister said.

“Putin is playing a game here and I’m sure that the American president won’t be able to sit and watch for much longer,” Boris Pistorius told German broadcaster ZDF.

The EU’s foreign policy chief Kaja Kallas said she would present a proposal to European leaders in Brussels later on Thursday to provide Ukraine with two million rounds of large-calibre artillery ammunition, according to a letter seen by Reuters.

-with AAP