This illustration picture taken on April 6, 2018 in Moscow shows the Telegram messenger application displayed on the screen of a smartphone. (AFP Photo) |
The Roskomnadzor telecoms watchdog, which brought the case, had earlier demanded the service be blocked as soon as the verdict was announced.
Telegram's self-exiled Russian founder Pavel Durov has long said he will reject any attempt by the country security's services to gain backdoor access to the app.
The free application, which lets people exchange messages, photos and videos in groups of up to 5,000 people, has attracted more than 200 million users since its launch in 2013.
Telegram is especially popular among political activists of all stripes, but has also been used by jihadists.
In September 2017 the FSB security service demanded encryption keys, Durov said, prompting a formal complaint when the request was rejected.
Durov wrote last year that the FSB's demands are "technically impossible to carry out" and violate the Russian Constitution which entitles citizens to privacy of correspondence.
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