Telegram founder Pavel Durov said Thursday that Russian authorities had designated him a "terrorist" after he refused to comply with Moscow's demands for mass surveillance and censorship on the messaging platform, accusing the Kremlin of seeking tighter control over online communications.

"Russia has designated me as a 'terrorist' for refusing its demands for mass surveillance and censorship on Telegram," he said on his platform.

Earlier Thursday, Russia added Durov, 41, to a blacklist of "terrorists and extremists," a day after saying it was seeking his arrest over accusations he let his platform be used by Ukrainian intelligence.

Durov, who has lived outside Russia for years, holds French and United Arab Emirates passports.

He said that under Russian law, he was now banned from 'publishing information on the Internet."

"Russian officials have clearly got confused about who can ban whom from the Internet," he quipped.

Since the Kremlin invaded Ukraine in 2022, Telegram has emerged as a crucial platform used by pro-war bloggers to justify Moscow's invasion and sow disinformation in Ukraine and the West.

Telegram has also been used as a top communication tool by Russian soldiers in Ukraine.

Moscow for years tried and failed to block Telegram.

Russian authorities have recently been pushing users to switch to an unencrypted state-backed messenger, named Max, which Durov has dismissed as "built for surveillance and political censorship."