Russia’s media watchdog has threatened to slow down the speed of Google if it fails to delete what it calls “unlawful content.”
Roskomnadzor has given Google 24 hours to remove videos it says relate to drugs, violence and extremism.
Google – which owns YouTube – could be fined between 800,000 and 4 million roubles (£7,700 – £38,000) by the service.
The tech firm has been approached for comment.
Roskomnadzor sent more than 26,000 notices to Google to delete what it called “illegal information,” the watchdog said in a statement reported by state-run news agency TASS.
The statement also accused Google of restricting YouTube access to Russian media outlets, including RT and Sputnik, and supporting “illegal protest activity.”
If Google does not act, the watchdog said it could also slow down internet speeds for users in Russia trying to access Google.
The state has already used these powers in March, to restrict access to Twitter after Roskomnadzor said it failed to remove around 3,000 posts.
Internet service providers in Russia can limit or block the flow of data to websites, making connections slower when accessing certain pages.
Google is currently suing Roskomnadzor over demands that it removes content, according to court documents seen by Reuters.
The case involves twelve YouTube videos which include encouraging minors to join unsanctioned protests in January, in support of jailed Kremlin critic Alexei Navalny.
Mr Navalny has more than 6.5 million subscribers on YouTube, and regularly posts videos on the platform voicing his opposition to President Vladimir Putin and the Russian government.
A hearing has been scheduled for 14 July.