U.S. President Donald Trump's special envoy Steve Witkoff is expected to visit Moscow on Wednesday, according to Russia's state news agency.
Meanwhile Ukrainian officials say the American president spoke to Ukrainian President Volodymyr Zelensky on Tuesday.
Mr Trump has set a deadline of Friday for Russia to agree to end the Ukraine war or face new sanctions.
Kate Fisher reports from Washington
IN: President Zelensky
OUT: SOC
DUR: 00:53