US President Donald Trump said that the US would help Europe in providing security for Ukraine as part of any deal to end Russia's war in Ukraine.
But he also suggested to reporters that he no longer believed reaching a ceasefire was a necessary prerequisite for striking a peace agreement, backing a position staked out by Russian President Vladimir Putin and opposed by Ukraine's President Volodymyr Zelensky and most European leaders.
"When it comes to security, there's going to be a lot of help," Mr Trump said, adding that European countries would be involved.
"They are a first line of defence because they're there, but we'll help them out."
The two presidents took questions from the media in the Oval Office before meeting in private, six months after their last appearance there descended into disaster when Mr Trump and Vice President JD Vance upbraided Mr Zelensky in an extraordinary public dressing-down.
Watch: Trump says Putin will accept security guarantees for Ukraine
This time, the meeting appeared far more convivial, despite the US President's movement toward Russia in recent days following his summit in Alaska with Mr Putin.
Mr Zelensky struck a deferential tone, expressing gratitude more than once for the support of the US.
Mr Zelensky was also backed by the leaders of Britain, Germany, France, Italy, Finland, the European Union and NATO, who travelled to Washington to demonstrate solidarity with Ukraine and push for strong security guarantees for the country in any post-war settlement.
Following their one-on-one discussion, Mr Trump and Mr Zelensky made a joint appearance with the European leaders ahead of planned multilateral talks.
Zelensky says discussion was 'very good'
Mr Zelensky described the one-on-one discussion as "very good" and said they had spoken about the importance of US security guarantees for Ukraine.
"This is very important, that the United States gives such a strong signal and is ready for security guarantees," Mr Zelensky said.
Mr Trump said he and Mr Zelensky had covered "a lot of territory" during their discussion.

He also again proposed a three-way summit among Mr Putin, Mr Zelensky and himself aimed at reaching a peace deal, which Mr Zelensky said he would support.
Mr Putin has not publicly committed to such a meeting, though Mr Trump said repeatedly that he believes Mr Putin wants to end the war.
Mr Trump said he had spoken to Mr Putin and would call him after the talks as well.

Mr Trump is pressing for a quick end to Europe's deadliest war in 80 years, and Kyiv and its allies worry he could seek to force an agreement on Russia's terms after the president on Friday in Alaska rolled out the red carpet - literally - for Mr Putin, who faces charges from the International Criminal Court (ICC) for war crimes.
Mr Trump said in the Oval Office that he liked the concept of a ceasefire, but they could work on a peace deal while the fighting continued.
"I wish they could stop, I'd like them to stop," he said. "But strategically that could be a disadvantage for one side or the other."
During the later appearance, French President Emmanuel Macron and German Chancellor Friedrich Merz pushed back on that suggestion.
"I can't imagine that the next meeting would take place without a ceasefire," Mr Merz said. "So let's work on that and let's try to put pressure on Russia."
Russian attacks overnight on Ukrainian cities killed at least 10 people, in what Mr Zelensky called a "cynical" effort to undermine talks.
Warm greeting
Mr Trump greeted Mr Zelensky warmly outside the White House, expressing admiration for Mr Zelensky's black suit, a departure from his typical military clothes.
When a reporter asked Trump what his message was to the people of Ukraine, he said, "We love them." Zelenskiy thanked him, and Trump put his hand on Zelenskiy's back in a show of affection before the two men went inside to the Oval Office.
Reporter tells Zelensky he looks 'fabulous' in suit
Mr Trump has rejected accusations that the Alaska summit had been a win for Mr Putin, who has faced diplomatic isolation since Russia's invasion of Ukraine in 2022.
"I know exactly what I'm doing, and I don't need the advice of people who have been working on all of these conflicts for years, and were never able to do a thing to stop them," Mr Trump wrote on social media.
Mr Trump's team has said there will have to be compromises on both sides to end the conflict.
But the president himself has put the burden on Mr Zelensky, saying Ukraine should give up hopes of getting back Crimea, annexed by Russia in 2014, or of joining the NATO military alliance.
Mr Zelensky has already all but rejected the outline of Mr Putin's proposals from the Alaska meeting.
Those include handing over the remaining quarter of its eastern Donetsk region, which is largely controlled by Russia.

Any concession of Ukrainian territory would have to be approved by a referendum.
Ukraine and its allies have taken heart from some developments, including Mr Trump's apparent willingness to provide post-settlement security guarantees for Ukraine, though the details remain unclear.
The war, which began with a full-scale invasion by Russia in February 2022, has killed or wounded more than a million people from both sides, including thousands of mostly Ukrainian civilians, according to analysts, and destroyed wide swaths of the country.
Mr Putin faces an arrest warrant from the ICC over the abduction and deportation of Ukrainian children, adding controversy to Mr Trump's decision to invite him to Alaska.
Mr Zelensky said he and Mr Trump discussed the issue of missing children during their meeting.
Russia, which is not part of the ICC, denies the allegations.
Russia has been slowly grinding forward on the battlefield, pressing its advantages in men and firepower.
Officials in Ukraine said a drone attack on a residential complex in the northern city of Kharkiv killed at least seven people, including a toddler and her 16-year-old brother.
Strikes in the southeastern city of Zaporizhzhia killed three people, they said.
Ukraine's military said that its drones had struck an oil pumping station in Russia's Tambov region, leading to the suspension of supplies via the Druzhba pipeline.