"Roskomnadzor has ordered telecommunications service providers to limit access to the webpages at navalny.com, mentioned in the ruling issued by the Krasnodar region's Ust-Labinsky District Court".
YouTube and Instagram may be blocked in Russian Federation as early as Wednesday unless they comply with the order and remove the material, Vedomosti newspaper reported.
The lawsuit in question was filed on February 9 against Anastasia Vashukevich and Alexander Kirillov, who had posted private photos of Oleg Deripaska on their social media accounts, as well as audio recordings of his conversations, thus violating his privacy.
Deripaska previously invested in a private equity firm run by former Trump campaign manager Paul Manafort, who also offered him "private briefings" on the campaign in July 2016.
YouTube and Instagram face being blocked by Russian internet service providers as a result of a standoff between one of the country's richest businessmen and an opposition leader.
Instagram has not yet commented on the matter but an anonymous source from YouTube claims that, whilst it has sent messages to those who uploaded the videos, it has not asked them to remove them.
If neither Mr Navalny nor the United States tech firms involved delete or otherwise block local access to the imagery by the end of the day, then Russia's ISPs will be required to take action themselves.
Russian Federation has threatened to shut down YouTube and Instagram unless they agree to remove a video accusing Deputy Prime Minister Sergey Prikhodko of corruption.
Navalny's report caused a potentially embarrassing splash ahead of a March 18 election in which Putin, who has been president or prime minister since 1999, appears certain to win a new six-year term but is said to be hoping for a convincing victory that would strengthen his mandate and further cement his power.
The material was said to have been sourced from a woman's Instagram account, where it had been posted in 2016.
The next day, Mr Deripaska obtained a court order demanding the removal of 14 Instagram posts and seven YouTube clips.
"Roskomnadzor has blocked https://navalny.com/ at the request of (Russian oligarch Oleg) Deripaska", Navalny said on Twitter.
Navalny in trouble with Russian government and Google over video supposedly capturing a hush-hush meeting on a yacht. "Since not all internet service providers in Russian Federation are able to cut access to individual web pages, they may be forced to block YouTube and Instagram if the companies fail to comply with the Roskomnadzor order". But he has been barred from standing against President Putin in next month's election because of a corruption conviction, which he says is politically motivated.