At least one person was killed and 71 wounded in Russian drone attacks on the northeast Ukrainian city of Kharkiv, officials said on Monday, and President Volodymyr Zelenskiy called for more support from Kyiv's allies.

Russia's intensified drone and missile attacks on Ukraine have killed at least 10 civilians, prompting a major Ukrainian counterstrike and raising global concerns over escalating warfare.

Russia launched 550 drones and missiles across Ukraine overnight in the largest aerial assault since the war began. The capital Kyiv was the primary target.