Vladimir Putin has sent a dire warning to Donald Trump that there will be "extremely harmful consequences" if the US attacks Iran again, according to reports.

It came as the pair discussed the war in Iran and floated a temporary ceasefire in Ukraine in a 90-minute phone call on Wednesday.

Putin’s foreign policy adviser said the Russian president said Moscow viewed the prospect of a US ground operation in Iran as dangerous.

Russian media reported that he told Trump that he foresees "extremely harmful consequences" if the US and Israel attack Iran again, calling any ground operation or invasion "extremely dangerous and unacceptable".

Trump later said: “We had a very good conversation, I’ve known him a long time.”

He added that Putin offered to take Iran’s buried uranium to Russia, but Trump said he preferred for the Russian president to be “involved with ending the war in Ukraine”.

“I said, before you help me, I want to end your war,” said Trump.

The American president, who has long spoken of his friendship with the Russian leader, said he thinks they will “come up with a solution relatively quickly” to the war in Ukraine.

Trump added that he had “suggested a little bit of a ceasefire” and said Putin “might do that.”

He also insinuated – as he has before – that Ukraine’s President Volodymyr Zelenskyy was at fault for not agreeing to a peace deal.

A Russian official said the pair had discussed a potential temporary truce in Ukraine to mark the anniversary of the end of World War II next month.

A similar proposal was tabled last year, but never came to fruition.

It came following a historic speech by King Charles to Congress in which he called for "unyielding resolve" in the continued defence of Ukraine and its people.