Earlier this month, Trump set a 50-day deadline for Russia to accept a ceasefire. Failure to do so, the president said, would prompt punishing new economic measures, among them secondary sanctions on nations doing business with Moscow.

The Kremlin said on Tuesday that it had "taken note" of a statement by U.S. President Donald Trump that he was shortening his deadline for Moscow to sign up to a ceasefire in Ukraine or face sanctions.