Russia launched several waves of drone attacks on Kyiv early on Sunday for the second night in a row, stepping up its assaults on the Ukrainian capital after several weeks of pause, the city's military administration said.

Axar.az reports that Popko said that according to preliminary information, Ukraine's air defense systems hit close to 10 Iranian-made Shahed kamikaze drones in Kyiv and its outskirts.

"The enemy's UAVs (unmanned aerial vehicles) were launched in many groups and attacked Kyiv in waves, from different directions, at the same time constantly changing the vectors of movement along the route," Serhiy Popko, head of Kyiv's military administration, said on the Telegram messaging app.

"That is why the air raid alerts were announced several times in the capital."

There have been no initial reports of "critical damage" or casualties, he said.

Reuters could not independently verify the reports. There was no immediate comment from Russia.