Russia's state media regulator has asked a court to block the messaging app Telegram following the company's refusal to give the Federal Security Service (FSB) access to users' messaging data.
Telegram is widety used countries across the former Soviet Union and Middle East, and reportedly has 200 million active users as of March this year, making it the ninth most popular messaging app in the world.
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.
Telegram has consistently refused to comply with its demands, citing respect for user privacy.
The Russian Communications Agency said on Friday it has filed a lawsuit against the messaging app Telegram after it refused to hand over encryption keys to Russian intelligence. "Telegram Messenger Limited Liability Partnership".
Telegram's lawyer Pavel Chikov last month said: "The FSB's argument that encryption keys can't be considered private information defended by the Constitution is cunning".
"The position of Telegram remains the same - the demands of the FSB (security service) to provide access to private conversations of users are unconstitutional, not based on the law, and can not be fulfilled technically and legally", said Pavel Chikov, who leads a human rights group representing the app.
President Vladimir Putin's spokesman Dmitry Peskov on Friday said the service was a convenient tool to communicate with journalists and it would be a "shame" if an agreement between the app and authorities could not be reached. Co-founder Pavel Durov, who lives in self-imposed exile overseas, said after the Supreme Court ruling that his company would not provide the FSB with encryption keys.
From this year they must also store all the data of Russian users inside the country, according to controversial anti-terror legislation passed in 2016 which was decried by internet companies and the opposition.