Ukraine and Russia targeted each other with long-range strikes, officials said Monday, amid continuing uncertainty about whether an agreement to stop their more than three-year war is within reach at the start of what America’s top diplomat called a “very critical” week.

Russia said on Monday it was waiting for a signal from Ukraine regarding Kyiv's willingness to hold direct negotiations to end the war, but said it did not so far see any signs of movement. The Kremlin said last Friday that the possibility of direct talks between the two sides had been raised during a three-hour meeting between President Vladimir Putin and U.