Trump on Monday said the United States would ship "billions of dollars' worth" of military equipment to NATO members, paid for by the alliance, to be handed over to Ukrainian forces battling grinding Russian advances. Trump had earlier this month suggested NATO would "100 percent" pay for U.S. weapons, which would be sent to Ukraine.

Trump said the United States would put secondary tariffs on countries that do business with Russia if a peace deal is not reached in 50 days.

The Kremlin said on Friday that it did not believe that a tougher stance U.S. President Donald Trump has adopted towards Russia over its war in Ukraine means the end of U.S-Russia talks aimed at reviving their battered ties.