Air raid sirens and explosions were reported across Ukraine on Friday, including in the capital city of Kyiv, according to Interfax Ukraine and social media posts. There were no immediate details on what had been struck or any resulting damage and casualties, but the city's military administration confirmed that anti-aircraft units were in operation.

Interfax reported that explosions were also heard after midnight in several other cities, including Dnipro, Kremenchuk, and Poltava in central Ukraine, as well as in Mykolaiv in the south. Unidentified airborne objects were said to be heading towards the west of the country, according to Telegram messages quoted by Interfax.

The reported attacks come a day after the Kremlin said it would welcome anything that could bring an end to the conflict in Ukraine, following a phone call between Ukrainian President Volodymyr Zelenskiy and Chinese President Xi Jinping. It was the first time the leaders had spoken since Russia invaded Ukraine in February last year.

However, the Kremlin reiterated its commitment to achieving the aims of its "special military operation" in Ukraine, which it launched on Feb. 24, 2022, citing the need to protect Russia. Ukraine and its Western allies have condemned the invasion as an unprovoked land grab by Russian President Vladimir Putin, resulting in the biggest land war in Europe since World War Two.

Russian forces have reportedly faced setbacks in the conflict and have been trying for 10 months to gain control of the shattered remains of Bakhmut, a city of 70,000 people. The city is seen as a key objective for Russia in its efforts to control other cities in eastern Ukraine.