The Federal Service for Supervision of Communications, Information Technology and Mass Media also known as Roskomnadzor, said in a statement on its website that it had sent teleco operators a notification about blocking access to Telegram inside Russian Federation.
The Virgin Islands-registered company said last month its total audience globally surpassed 200 million users, driven by attention for the world's largest initial coin offering. "It will take several hours because the operators are removing it, and the blocking process will be gaining momentum", Zharov said.
Smolina said that Telegram should be blocked immediately despite rules under which Russian court decisions normally come into effect after appeals are exhausted. Telegram refused each time, arguing that it would give the FSB access to all encrypted chats between its users.
On April 6, Roskomnadzor filed the lawsuit on the blocking of Telegram in Russian Federation. Telegram said those demands would be impossible to implement since the keys were stored on users' devices.
The FSB first asked the app to provide information to decode messages sent by six telephone numbers linked to members of terrorist organisations in Russian Federation, including the suicide bomber behind the terror attack on St Petersburg's metro in April 2017, in which 15 people died.
He further elaborated that the ban would not affect the terrorist threat in Russian Federation, as "extremists will keep using encrypted communication channels either in other messengers or via VPN".
"We consider the decision to block the app to be unconstitutional and we will continue", he said in a statement posted on social media Monday. Reportedly, government officials access the app via a VPN - a technique commonly used in Russian Federation to circumvent internet restrictions - to communicate with the media and coordinate timing for conference calls.
Telegram is widely used in countries across the former Soviet Union and Middle East.
Russia's communications watchdog has started to enforce a nationwide ban on popular messaging application Telegram. But on Monday, the Russian Federation spokesman's office said it will now start using a different app.