Moscow’s forces have been recapturing some villages and land taken in a Ukrainian incursion into Russia. The advances could undermine Kyiv’s hopes of pushing Russia to the negotiating table.

Serhii Popko, head of the Kyiv City Military Administration, said air raid alerts lasted for two hours in the Ukrainian capital, but that air defenses destroyed all of the drones that targeted the area.

Kyiv has frequently accused Russian of executing captured Ukrainian troops - a war crime under the Geneva Convention. Earlier this month the prosecutor general's office alleged that Russian forces had executed 93 Ukrainian soldiers since the beginning of the conflict.

The U.S. says it is "concerned" about reports of North Korean soldiers fighting alongside Russian troops in the war against Ukraine, calling it "a new level of desperation."