US Secretary of State Marco Rubio has accused Ukrainian President Volodymyr Zelensky of lying over US demands and voiced openness to diverting weapons to Kyiv to support the US attack on Iran.
Mr Zelensky had said in an interview the United States was pressing Ukraine to give up the eastern Donbas region to Russia, which invaded four years ago, before finalising any post-war security guarantees to Kyiv.
"That's a lie," Mr Rubio told reporters when asked about Mr Zelensky's remarks.
"I saw him say that and it's unfortunate he would say that because he knows that's not true," Mr Rubio said in Paris after talks of the Group of Seven industrialised democracies.
He said: "What he was told is the obvious: security guarantees are not going to kick in until there's an end to a war because otherwise you're getting yourself involved in the war.
"That was not attached to, unless he gives up territory.
"I don't know why he says these things. It's not true."
The attack on Mr Zelensky was especially striking coming from Mr Rubio, a former hawkish senator who has largely been seen as more supportive of the Ukrainian cause than some others in US President Donald Trump's circles.
In a scene that went viral in February last year, Mr Rubio sat in the Oval Office as Mr Trump and Vice President JD Vance berated Mr Zelensky, saying he was ungrateful for US assistance.
Recently, Mr Trump has again criticised the Ukrainian president, saying that he needs to accept compromises and comparing him unfavourably with Russian President Vladimir Putin.
Mr Rubio said that the United States was open to shifting assistance to Ukraine after the United States and Israel attacked Iran.
"Nothing yet has been diverted, but it could," Mr Rubio said.
"If we need something for America and it's American, we're going to keep it for America first," he added.
But he said there had not yet been any change to the so-called Prioritised Ukraine Requirements List, a NATO initiative established after Mr Trump's return, in which European allies fund weapons requested by Ukraine that are purchased from the United States.
