An Apple logo is pictured in an Apple store in Paris, France September 17, 2021. REUTERS/Gonzalo Fuentes

By Mark Trevelyan and Gleb Stolyarov

Dec 4 (Reuters) - Russia has blocked Apple's video-calling app FaceTime, the state communications watchdog said on Thursday, as part of an accelerating clampdown on foreign tech platforms that authorities allege are being used for criminal activity.

The move follows restrictions against Google's YouTube, Meta's WhatsApp and the Telegram messaging service.

Critics say the curbs amount to censorship and a tightening of state control over private communications. Russia says they are legitimate law enforcement measures. Russian authorities have this year launched a state-backed rival app called MAX, which critics say could be used for surveillance - allegations that state media have dismissed as false.

Justifying its decision, the communications regulator, Roskomnadzor, said in an emailed statement: "According to law enforcement agencies, FaceTime is being used to organise and carry out terrorist attacks in the country, recruit perpetrators, and commit fraud and other crimes against Russian citizens."

The watchdog did not cite evidence in support of the allegations.

Apple representatives did not immediately respond to requests for comment on the blocking of FaceTime, an app that enables users to make free video and audio calls over Wi-Fi or cellular data.

Moscow residents who tried FaceTime on Thursday reported seeing an on-screen message saying "User unavailable". One said a friend that she tried to contact had seen the incoming call but was unable to connect.

In recent months, Roskomnadzor has intensified measures to block access to Western media and tech platforms it says are hosting content that breaches Russian laws.

In August, Russia began limiting some calls on WhatsApp and Telegram, accusing them of refusing to share information with law enforcement in fraud and terrorism cases. Roskomnadzor last week threatened to block WhatsApp completely.

On Wednesday, Roskomnadzor blocked access to the U.S. children's gaming platform Roblox, accusing it of distributing extremist materials and "LGBT propaganda". Roblox said it respects the laws of countries where it operates and is deeply committed to ensuring users' safety.

(Reporting by Mark Trevelyan in London and Gleb StolyarovEditing by Tomasz Janowski)