Intelligence officials have long warned of what they see as the dangers of the information leaked by Mr Snowden and its potential impact on keeping people in the UK safe – a concern Prime Minister David Cameron has said he shares.
According to the Sunday Times, Western intelligence agencies have been forced to pull agents out of “hostile countries” after “Moscow gained access to more than one million classified files” held by Mr Snowden.
“Senior government sources confirmed that China had also cracked the encrypted documents, which contain details of secret intelligence techniques and information that could allow British and American spies to be identified,” the newspaper added.