Facebook and Twitter have been blocked in Russia by the country’s communications regulator amid tensions over the war in Ukraine.

Roskomnadzor said its decision over Facebook was in response to what it claimed was restricted access to Russian media on the social media platform.

According to the regulator, there have been 26 cases of discrimination against Russian media by Facebook since October 2020, with access restricted to state-backed news outlets including RT, Sputnik, RIA, the defence ministry’s Zvezda TV, and websites gazeta.ru and lenta.ru.

Roskomnadzor later said it also cut access to Twitter in line with a decision by the Russian prosecutor general’s office.

The watchdog has previously accused the platform of failing to delete content banned by Russian authorities.

Reacting to the Russian decision over Facebook, the US said it was “deeply concerned” by the move, saying it was part of broader attempts to prevent its citizens getting information.

“This is part of their effort…to cut off a range of information from their public,” White House spokesperson Jen Psaki said.

“We are deeply concerned about this and concerned about the threat on freedom of speech in the country.”

Meta runs Facebook, Instagram, and WhatsApp. Meta’s president of global affairs, Sir Nick Clegg, said the company would continue to do everything it could to restore its services.

Reacting to the regulator’s decision, he tweeted: “Soon millions of ordinary Russians will find themselves cut off from reliable information, deprived of their everyday ways of connecting with family and friends and silenced from speaking out.

“We will continue to do everything we can to restore our services so they remain available to people to safely and securely express themselves and organise for action.”

It comes as Russia seeks to control the spread of information on the invasion of Ukraine and to move against independent news sources. It follows the blocks imposed earlier on Friday on the BBC, the US government-funded Voice of America and Radio Free Europe/Radio Liberty, German broadcaster Deutsche Welle, and Latvia-based website Meduza.

Last Friday, Moscow said it was partially limiting access to Facebook, a move the company said came after it refused a government request to stop the independent fact-checking of several Russian state media outlets.

By Saturday, Twitter also said its service was being restricted for some Russian users.