Russia will block access to Facebook next year unless the social network complies with a law that requires websites which store the personal data of Russian citizens to do so on Russian servers, Russian news agencies reported on Tuesday.

The threat was made by Russia's communications watchdog Roskomnadzor, agencies said, the organisation which blocked access to LinkedIn's website last November in order to comply with a court ruling that found the social networking firm guilty of violating the same data storage law.

That case set a precedent for the way foreign Internet firms operate in Russia and other companies are now under pressure from the regulator to comply with the law, which was approved by President Vladimir Putin in 2014 and entered into force in September 2015.