This is because Telegram has refused to give the Russian state security access to its encryption keys which would give them the ability to decrypt and read messages sent using the service.
Smolina said that Telegram should be blocked immediately despite rules under which Russian court decisions normally come into effect after appeals are exhausted.
Russian Federation implemented strict anti-terrorism laws in 2016, which required messaging services to provide authorities with the ability to decrypt messages.
Russian web service providers now have 24 hours to fulfill the order.
A Moscow court has ordered that chat app Telegram, which has raised $1.7 billion in its pre-initial coin offering, be blocked by Russia's telecommunication companies.
Interfax news agency quoted an official at the watchdog as saying it would take several hours to complete the operation to block access.
Russia's communications watchdog has started to enforce a nationwide ban on popular messaging application Telegram.
Pavel Chikov, the lawyer who represented Telegram's interests during the court dispute with the authorities, wrote on Twitter on Monday morning that the Telegram.org website had become unavailable.
The judge further observed that the court's verdict ought to be implemented instantly.
Roskomnadzor claimed that Telegram had not been entirely honest in its statements, as some unnamed experts said that it is still possible to give the security services some keys allowing secret messages to be decoded. Durov has long said he will reject any attempt by the country's security services to gain backdoor access to the app.