Roskomnadzor said its lawsuit, which aims to "restrict access" to Telegram in Russian Federation, was connected to statements by the FSB that the app was not complying with its legal requirements as an "organiser of information distribution".
Telegram first attracted the attention of the watchdog in 2016 when it failed to comply with new legislation related to terrorism.
All of this started a year ago when the FSB, the successor to the KGB, demanded that the founder, Pavel Durov, hand over encryption keys to the service.
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Telegram's lawyer Pavel Chikov said the defense was planning to present objections to the court.
Back in March, Telegram lost an appeal in Russian Federation after the country's Supreme Court ruled that it must continue providing user data to the country's security services, the FSB, so that it prevent terrorist attacks.
The Roskomnadzor report also said that the above duties had to be fulfilled within 15 days from the day the notification was received under part 1 of Art. 15.4 of Law No. 149.
Founded by Russian entrepreneur Pavel Durov, Telegram said it has 200 million users around the world. It's already battled with Instagram and YouTube earlier this year over videos uploaded by political activist Alexei Anatolievich, while Twitter and Facebook have agreed to host user data locally to comply with encryption laws. The service now has over 200 million active monthly users. Trying to fight Russian pressure, Telegram filed a lawsuit against the Russian government at the European Court of Human Rights (ECHR).
Telegram is also now trying to raise funds for expansion via an Initial Coin Offering.