Russian President Vladimir Putin has called on Ukrainian troops in the Russian region of Kursk to surrender, as diplomatic back-and-forth continues over a potential US-brokered ceasefire with Ukraine.

U.S. officials were in Moscow for talks, and the Russian leader said he was open to a cease-fire, but President Volodymyr Zelensky of Ukraine expressed skepticism.

Russia's Security Council's Deputy Chairman Dmitry Medvedev attends a meeting of the Council for Science and Education at the Joint Institute for Nuclear Research in the Moscow region's city of Dubna,