But on the issue of whether there is mass surveillance - a claim made on the basis of documents provided by US whistleblower Edward Snowden - the Commissioner essentially gives Britain, and particularly GCHQ, a clean bill of health.

"I can assure anyone who is not associated with terrorists or serious criminals that the agencies have no interest whatever in examining their private communications and for practical purposes, do not do so," he said.

Sir Anthony acknowledged there were legitimate concerns which need to addressed, but said he believed the current legal framework - the Regulation of Investigatory Powers Act 2000 - was broadly fit for purpose and being used correctly.

He found that even though so-called "general warrants" provide for large-scale collection of material, this was primarily focused on foreign traffic, and GCHQ cannot indiscriminately trawl through it.

As a result, he said, there was no "sentient" intrusion into the private affairs of UK citizens - in others words by a person rather than in automated fashion by a computer.

He also said he has found no evidence that GCHQ was evading the law by getting material from the US that it does not have the power to access itself.

Home Secretary Theresa May said the report "makes clear the intelligence agencies, law enforcement agencies and other public authorities operate lawfully, conscientiously and in the national interest".

Foreign Secretary William Hague, the minister responsible for GCHQ, said: "A senior and fully independent judge has looked in detail at whether the interception agencies 'misuse their powers to engage in random mass intrusion into the private affairs of law abiding UK citizens'.

"He has concluded that the answer is 'emphatically no'.

"We are open to suggestions to strengthen the oversight framework even further and make it as transparent as possible without putting security at risk."