The Kremlin said on Tuesday that Ukraine had not responded to many offers by Russia President Vladimir Putin to start direct peace negotiations, and that it was unclear whether it would join a three-day ceasefire he has announced for next month.

Russian President Vladimir Putin declared a three-day ceasefire in the war with Ukraine next month to celebrate the Soviet Union’s victory over Nazi Germany during World War II.

Russian President Vladimir Putin announced a three-day ceasefire to coincide with the 80th anniversary of the Soviet Union’s victory over Nazi Germany, even as President Donald Trump has expressed growing impatience with the stalled efforts to reach a peace agreement.