The plan appears to repeat Russia's maximalist terms -- demands consistently rejected by Ukraine as tantamount to capitulation.

The draft provides for "recognition of Crimea and other regions that the Russians have taken" and "reduction of the army to 400,000 personnel", the source, who does not wish to be identified, told AFP.

The plan would also see Ukraine giving up all long-range weapons.

"An important nuance is that we don't understand whether this is really Trump's story" or "his entourage's", the official added.

It was "unclear" what Russia was supposed to do in return, according to the source.

US media outlet Axios earlier reported Moscow and Washington had been working on a secret plan to end the almost four-year war. The Kremlin had declined to comment on the report, later saying there was nothing new in the peace settlement progress.

AFP has reached out to the White House for comment.

Russia now occupies around a fifth of Ukrainian territory -- much of it ravaged by fighting.

Moscow has repeatedly demanded it retains territory in southern and eastern Ukraine that it occupies and for Kyiv to cede even more land.

Moscow in 2022 annexed four Ukrainian regions -- Donetsk, Lugansk, Zaporizhzhia and Kherson -- despite not having full control over them.

Russia also annexed the Crimean peninsula from Ukraine in 2014 and has fully controlled it since then.

US President Donald Trump has sought to leverage his relationship with Russian leader Vladimir Putin to end the war, but has so far failed to make progress.

Since the start of his second term, Trump's position on the Ukraine war has shifted dramatically back and forth.