Fadeev also said Russia's stance on ending the war in Ukraine has not changed since Putin laid out his conditions last year: the full withdrawal of Ukrainian troops from parts of the Ukrainian regions of Donetsk, Zaporizhzhia and Kherson that they still control, and Ukraine abandoning its plans to join the NATO alliance.

President Donald Trump says there will be “very severe consequences” if Russian President Vladimir Putin does not agree to stop the war against Ukraine after the two leaders meet for a summit later this week in Alaska.

Trump, who described the call as "a ten", was urged to keep Ukraine's interests at the forefront when he meets Putin on Friday.