Ukrainian President Volodymyr Zelenskyy says he will urge allies to boost his country's air defenses at a meeting this week in Germany.

Russian forces continue to make costly but consistent gains in the Donetsk region in eastern Ukraine. They are steadily grinding down a pocket of resistance around the town of Kurakhove in the southern Donbas region and are also fighting to envelop the larger city of Pokrovsk to the north, Ukrainian soldiers and officials said.

Ukraine has launched a fresh offensive in Russia's Kursk region, the Russian defence ministry says. In a statement, the ministry said efforts to destroy the Ukrainian attack groups were ongoing. Officials in Ukraine have also suggested an operation is under way.

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.

Russia’s defence ministry may believe its forces are “defeating” Ukraine’s counter-offensive in the Kursk region, but Vladimir Putin clearly doesn’t.

Ukraine reportedly used U.S.-supplied ATACMS missiles to strike Russia’s Belgorod region, escalating tensions to new heights. Russia claims all eight missiles were intercepted by advanced air defense systems.