Fruitful discussions with Putin could end Ukraine war: Trump

US President Donald Trump said on Friday there is a "very good chance" the war between Russia and Ukraine can end after Washington had "productive" discussions with Russian President Vladimir Putin on Thursday.

He added that he had requested that Putin spare the lives of "completely surrounded" Ukrainian troops, apparently referring to Ukrainian forces being pushed back out of the Kursk region, their only foothold on Russian territory, reports Reuters.

"We had very good and productive discussions with President Vladimir Putin of Russia yesterday, and there is a very good chance that this horrible, bloody war can finally come to an end," Trump said in a Truth Social post.

White House spokeswoman Karoline Leavitt later told reporters that Trump had not spoken with Putin on Thursday, but that US envoy Steve Witkoff had.

Witkoff had a long meeting with Putin in Moscow on Thursday night, according to a source briefed on the matter who spoke on condition of anonymity.

Kremlin spokesman Dmitry Peskov said Putin had used the meeting to convey "signals" to Trump through Witkoff. He said Russia and the US would work out the timing of a phone call between their presidents once Witkoff had briefed Trump.

The US president has said he wants Moscow and Kyiv to agree a swift ceasefire to pause fighting in a conflict which he has warned has the potential to spiral into World War Three and has already cost many lives on both sides.