Previous Trump promises, threats and cajoling have failed to yield results., and the stubborn diplomatic stalemate will be hard to clear away. Meanwhile, Ukraine is losing more territory on the front line, although there is no sign of a looming collapse of its defenses.

President Trump has given an ultimatum to President Vladimir V. Putin of Russia to end the war in Ukraine or face U.S. sanctions.

U.S. President Donald Trump's special envoy Steve Witkoff is expected to visit Russia on Wednesday, state news agency TASS said on Monday, citing Russian and U.S. sources.

US President Donald Trump said Friday he was ordering two US Navy nuclear submarines to “appropriate regions,” in response to remarks by Dmitry Medvedev, Russia’s former president and current deputy chairman of its Security Council.

Russia said on Monday that everyone should be "very, very careful" about nuclear rhetoric, responding to a statement by U.S. President Donald Trump that he had ordered a repositioning of U.S. nuclear submarines.