The FSB has claimed that global terrorist groups actively use Telegram's secret chats with high levels of encryption. The FSB says telegram was also used by a suicide bomber who a year ago killed 15 people on a subway in St. Petersburg.
A Russian court on Friday ordered that access to the Telegram messenger service should be blocked in Russia, Russian news agencies reported, heralding communication disruption for scores of users - including government officials.
The court gave it 15 days to hand over the encryption keys.
Launched in 2013, Telegram is now among the world's most popular mobile messaging apps. According to a blog post attributed to Telegram founder Pavel Durov, the app has built-in workarounds for such bans.
Telegram co-founder Pavel Durov
But Russia's FSB Federal Security service has said it needs access to some of those messages for its work that includes guarding against terrorist attacks.
Telegram has also frequently hit the headlines over its use by terrorists, although that is more to do with its unencrypted "channels" feature, through which people can broadcast their opinions to followers. The company has a reputation for providing users with securely encrypted communication.
"My work is to fulfill this irreproachably in technical terms".
Well known for its secret chat functionality, Telegram couldn't have complied with the FSB's repeated requests without compromising its business model and entire approach to protecting privacy.
The feud between the Russian government and the house that Durov built is apparently going strong. The Russian Foriegn Ministry, for example, told readers on Telegram that they would be switching their Telegram service to Viber.