Meanwhile, Ukraine’s State Emergency Service said an 89-year-old woman was killed and two girls, aged two and 12, were among seven injured in a Russian strike on the southern port city of Mykolaiv overnight.

A woman and two girls, aged five and 10, were killed in a strike on a residential area in Sumy, and another four people were injured, it said.

Russian strikes also injured two people in the city of Bilhorod-Dnistrovskyi, while a food warehouse was set on fire in Dnipro, according to the State Emergency Service.

It comes a day after a busy beach in southern Russia was hit by a drone, killing seven people and injuring 58, according to Russian officials.

Social media footage verified by the BBC shows a drone crashing an exploding on a beach in the Krasnodar region as tourists look on from the shore and in the water.

Some Ukrainian Telegram channels have claimed it crashed onto the beach as a result of electronic warfare which jammed the drone’s signal, while eyewitnesses were quoted by Russian media as saying gunfire preceded the explosion, indicating that air defences may have tried to shoot the drone down.

The area’s regional governor accused Ukraine of “a deliberate strike on civilians”. Ukraine has not commented.

Both sides deny targeting civilians deliberately.