Telegram CEO and founder Pavel Durov says Apple has prevented the popular messaging service from updating globally since Russian authorities "ordered" the U.S. mobile-phone giant to remove Telegram from its app store.

Durov made the announcement on his official Telegram Channel on May 31, days after Russia's communications regulator said it had asked Apple to help it block Telegram in the country.

"Unfortunately, Apple didn’t side with us," Durov added, referring to Telegram's refusal to provide access to its encrypted communications to Russia's security agencies.

'Problematic Issue'

Roskomnadzor, the Russian communications regulator, said on May 28 that it had sent a letter to Apple asking that it to no longer make the free Telegram app available for download in Russia.

It said the U.S. firm was also asked to block push notifications for Telegram users in Russia, ensuring that Apple phone and tablet users do not receive alerts about new messages and rendering the application less useful.

Roskomnadzor said in its letter that Apple officials should "inform us as soon as possible about your company's further actions to resolve the problematic issue" with Telegram or face a "possible action by the agency."

A Moscow court last month banned Telegram following a long-running battle with authorities over its refusal to provide decryption keys for all its users’ communications.

'Troubled Country'

The ban has provoked repeated protests in Russia by thousands who use and support the popular messaging service.

Russian officials have claimed the ban against Telegram is justified because the service has been used in the planning of terror attacks around the world.

Durov on May 31 vowed to preserve "the right of our users to privacy in a troubled country.”

Telegram lets people exchange messages, stickers, photos, and videos in groups of up to 5,000 people. It has attracted more than 200 million users since its launch by Durov and his brother Nikolai in 2013.