US envoy Steve Witkoff will meet on Wednesday with Russian leadership in Moscow, an American source confirmed, as President Donald Trump's deadline to impose fresh sanctions over Russia's war in Ukraine looms.

U.S. special envoy Steve Witkoff will be in Moscow on Wednesday to meet with Russian leadership, a source familiar with the plan said on Tuesday.

Ukrainian President Volodymyr Zelensky said he held a "productive conversation" with his US counterpart Donald Trump on Tuesday ahead of a trip by Washington's Special Envoy Steve Witkoff to Moscow this week.