Russia says it will ban Facebook in 2018 if the social network fails to comply with local data storage laws.

Alexander Zharov, head of communications regulator Roskomnadzor, was quoted by official state media outlets on Tuesday as saying "the law is obligatory for all."

"In all cases we will make sure the law is complied with, or the company will stop working in the Russian Federation," he said. "There are no exceptions here."

Russia's law on personal data storage came into effect in September 2015. It requires companies that collect the personal data of citizens to store the information on Russian soil.

Zharov said his agency has not been in contact with Facebook (FB), but added that the company needs to comply with the law soon.

"In 2018, we will think about it, and maybe we will check," he said.

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Zharov told state media that Roskomnadzor had received a letter from Twitter (TWTR) saying it would comply with the data storage law starting in 2018.

Facebook and Twitter both declined to comment.

LinkedIn, which was acquired by Microsoft (MSFT) in 2016, has already run afoul of the law. It was banned by Roskomnadzor in November 2016.

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Roskomnadzor did not respond to requests for comment on Tuesday.

Kremlin spokesman Dmitry Peskov said that Facebook is a commercial enterprise earning money in Russia, and therefore it must comply with the law.