Police responded to the scene in Belgrave Square after squatters took over the property on Monday morning.

A Ukrainian flag was hung from a window and a banner read "this property has been liberated".

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Deripaska, a 54-year-old industrialist who founded the aluminium giant Rusal, was added to the UK government's sanctions list on 10 March, following Russia's invasion of Ukraine.

The fate of his property portfolio in Britain remains unclear after the government said his assets would be frozen.

Police said they were called in the early hours of Monday after it was reported that the squatters had entered the multi-million-pound mansion, which is close to the home of numerous foreign embassies.

In a statement, the squatters - who described themselves as anarchists - said: "By occupying this mansion, we want to show solidarity with the people of Ukraine, but also the people of Russia who never agreed to this madness.

"You occupy Ukraine, we occupy you."

The squatters said the mansion would "serve as a centre for refugee support" and that other properties would also be targeted.

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London High Court documents from 2007 identified Deripaska as the beneficial owner of the Belgrave Square mansion.

Representatives of Deripaska have not yet responded to a request for comment.

Shortly before the sanctions were imposed, Deripaska said peace was needed as soon as possible in Ukraine and warned that Russia would be different after the conflict.