Russian state media report that President Vladimir Putin has paid a surprise visit to Mariupol, a Ukrainian port city captured by Russian forces after they pounded much of it to ruins.

An official video shows Mr Putin driving a car through streets at night and speaking to local people.

It would be Mr Putin’s first visit to a newly-occupied Ukrainian territory.

He is also reported to have met top military commanders in Rostov-on-Don, a Russian city just east of Mariupol.

Tass news agency says he travelled to Mariupol by helicopter. In the video he is in the car with Russia’s Deputy Prime Minister Marat Khusnullin, who explains how the city is being rebuilt.

Putin also appears to visit the Philharmonic Hall, which was used to stage trials of defenders of the Azovstal iron and steel plant, a huge industrial complex where Ukrainian troops held out before eventually surrendering.

UN analysis estimates that 90% of the buildings were damaged and around 350,000 people were forced to leave, our of a pre-war population of about 500,000.

The fighting saw Russia strike a Mariupol theatre where hundreds of civilians were sheltering. The building collapsed, and at least 300 are believed to have died there.

Ukraine and human rights groups say the attack amounted to a war crime.

It is among incidents for which Mr Putin and his regime could be held legally responsible, the United Nations has said.

The International Criminal Court said on Friday it had issued a warrant for the arrest of Mr Putin over involving the illegal deportation of Ukrainian children to Russia. It means he could now be arrested if he sets foot in any of the court’s 123 member states.

On Saturday Mr Putin made an unannounced visit to Crimea, to mark the ninth anniversary of Russia’s annexation of the territory from Ukraine.

He visited a new Russian arts school, a children’s summer camp and future cultural projects, such as the New Russia museum and museum of Christianity, Russian state media reported.

The Kyiv authorities have vowed to liberate all Russian-occupied territories, including Crimea, which was annexed by Russia in 2014.