Russia has blocked the popular website of opposition leader Alexei Navalny over his investigation of an oligarch connected to former Trump campaign manager Paul Manafort.

The state communications oversight agency banned Navalny.com after oligarch Oleg Deripaska won a court decision against the investigation published there, which his representative told The Telegraph included “outrageous false accusations”.

The anti-corruption activist, who has been calling for a boycott of March's presidential election after he was barred from challenging Vladimir Putin, had found a model's Instagram videos of Mr Deripaska discussing US relations with deputy prime minister Sergei Prikhodko, a former foreign policy advisor to Mr Putin.

The conversation took place on Mr Deripaska's yacht off the coast of Norway in August 2016, Mr Navalny claimed using photos and ship and flight records. That was a month after Mr Manafort allegedly offered the oligarch private briefings on Donald Trump's campaign.

The metals magnate has denied receiving these briefings but admitted he had hired Mr Manafort as a consultant. He sued Mr Manafort last month for allegedly defrauding him of $18.9 million.