Manafort, who served as Trump’s campaign chief in mid-2016, is suspected of having offered information on the campaign to metals tycoon Deripaska. The offer was seen in Washington as evidence of Russia’s suspected interference in the U.S. presidential elections which saw Trump win the White House.

Deripaska in an Instagram post on Friday denied the allegations and called them part of a slander campaign against him.

Opposition leader Alexei Navalny has published a video investigation claiming that Russian oligarch Oleg Deripaska acted as a messenger between U.S. President Donald Trump’s ex-campaign chief Paul Manafort and a top Kremlin foreign policy official.

In his investigation released on Thursday, Navalny said he found the trail in a video posted by a self-described "sex huntress" on social media depicting Deripaska and Russia’s Deputy Prime Minister Sergei Prikhodko aboard a yacht in August 2016.

In July 2016, Manafort offered private briefings to Deripaska on the Trump campaign’s progress in an email, The Washington Post reported last year.

Navalny’s investigation alleges that the footage of Deripaska’s yacht meeting with Prikhodko, who served as a foreign policy advisor to Russian leaders for more than two decades, proves the oligarch’s role as a conduit between the Trump campaign and the Kremlin.

"[It’s] because these briefings were actually for Putin, the Kremlin, the Federal Security Service," Navalny says in the video, without providing further evidence. The video had gathered some 470,000 views by Thursday afternoon.

In an emailed statement to the media, a spokesman for Deripaska denied the findings of Navalny's investigation, describing it as "scandalous and mendacious assumptions driven by sensationalism."

"We totally refute these outrageous false allegations in the strongest possible way,” the statement said.



Russia’s Central Elections Committee has barred Navalny from running in next month’s presidential elections, in which Putin is widely expected to win his fourth term.



Editor's note: This story has been updated to include a statement from Deripaska and his spokesperson.