U.S. President Donald Trump's decision to ramp up arms shipments to Ukraine is a signal to Kyiv to abandon peace efforts, Russia said on Thursday, vowing it would not accept the "blackmail" of Washington's new sanctions ultimatum.

This winter, he tried to humiliate Ukraine's president, and now allows arms transfers to Kyiv. Behind the dramatic shift in Trump's thinking.

Russia has continued its nightly bombardment of Ukraine after President Donald Trump announced his decision to supply Ukraine with new military equipment and the White House's threats of further economic measures against Moscow.