Russia said on Sunday that Ukraine had launched a counter-attack in the Kursk region, an area of western Russia from which Russian troops have been trying to eject Ukrainian forces for the past five months.

President Volodymyr Zelenskyy says he will urge allies to boost Ukraine’s air defenses at a meeting this week in Germany, while both sides said Kyiv’s forces pressed new attacks Sunday in Russia’s Kursk region.

The Kremlin on Saturday vowed "retaliation" for what it said was Ukraine's use of American-made Army Tactical Missile Systems against targets in a Russian border region.