The UK has withdrawn intelligence agents from "hostile countries" after Russia and China deciphered top-secret information contained in files leaked by former US National Security Agency (NSA) contractor Edward Snowden, according to the Sunday Times.
Russia and China have both succeeding in cracking encrypted documents which contain details of secret intelligence techniques which could allow British and US agents to be identified, the newspaper said citing officials.
The development forced western intelligence agencies to scale down their operations and pull out their spies.
Snowden is believed to have downloaded 1.7 million secret documents before he left the US and was eventually granted asylum in Moscow in 2013.
Aides in British Prime Minister David Cameron's office have confirmed the top-secret material is in the hands of spy bosses in Moscow and Beijing.
A senior government source told the BBC that agents were being moved as the countries have "knowledge of how we operate", but added there was "no evidence" any had been harmed.
Snowden, whom the United States wants to stand trial for his leaks, justifies his actions as protection of 'privacy and basic liberties' and insists NSA and British-based GCHQ are involved in massive secret surveillance programmes targeting millions of innocent people.
