Moscow has accused Poland of threatening to allow "terrorist acts" against Russian President Vladimir Putin's plane.

Trump wants Russia and Ukraine to freeze the war on the current battlelines, with Moscow holding a huge swathe of eastern Ukraine.

President Volodymyr Zelenskiy said Russia "almost automatically became less interested in diplomacy" due to the postponement of a decision by the U.S. administration on Tomahawk missiles for Ukraine.

Russia said Foreign Minister Sergei Lavrov and US Secretary of State Marco Rubio came to no agreement on a meeting during phone talks, casting a shadow over preparations for a planned summit between their presidents aimed at ending the war in Ukraine.

Donald Trump urged Volodymyr Zelenskyy to accept Russia’s terms for ending its war in a volatile White House meeting on Friday, warning that Vladimir Putin had said he would “destroy” Ukraine if it did not agree.

Poland warned Russia's President Vladimir Putin on Tuesday against travelling through its airspace for a summit in Hungary with U.S. President Donald Trump, saying it could be forced to execute an international arrest warrant if he did.

Kremlin envoy Kirill Dmitriev floated the tunnel idea late on Thursday after Putin spoke to Trump by phone and agreed to meet in Budapest.

Puck's Julia Ioffe joins Morning Joe to discuss her new book 'Motherland: A Feminist History of Modern Russia, from Revolution to Autocracy'.