Mr Shayler was charged with breaking the Official Secrets Act for making a series of claims about the working of the intelligence services.

He said members of MI6 aided an unsuccessful assassination attempt against the Libyan leader Colonel Muammar Gaddafi. The UK Government has denied any such plot.

David Shayler: "Legitimate criticism of the British state"

The government failed to have Mr Shayler extradited from France, where he now lives, unable to return to Britain for fear of arrest.

In an interview with BBC World's HARDtalk, filmed in Paris after his release from jail in December, he defended his actions.

He said: "I was hoping for something slightly different from a Labour Government that had been elected on a platform of commitment to freedom of information.

"All I'm doing is making legitimate criticism of the British state."

Mr Shayler has made repeated calls for a greater scrutiny of the secret services to prevent illegal activities and incompetence. He wants to see the government bring in a Freedom of Information Act, a Labour manifesto commitment.

He said: "I actually broke a law that wouldn't have been illegal 10 years ago, if you remember the 1980s when they took the public interest defence out of the Official Secrets Act.

"That meant that any divulgence of secrets at all would be illegal, whereas up until that point you could argue that if I was revealing something that was in the public interest I would have a defence to use in court."

On the run

Mr Shayler's allegations were first made in the Mail on Sunday in August 1997, for which he insisted he received no payment, only money for expenses - to help support him in his inevitable fugitive lifestyle.

He said: "The law makes no allowance for what I've done and if I'd stayed in the UK I could have been put in prison for 12 months on remand before I'd even been tried. So effectively even if I'd been found not guilty I still would have been in prison for 12 months and the government would have shut up a critic."

Mr Shayler stood by his actions as a battle for democracy and told HARDtalk he had "no regrets."

"The service has tried to call me a traitor, which is actually wrong,"he said. "I came to a point in my life where I felt uneasy living with myself knowing about things like the Gaddafi plot for example, where the intelligence services had used taxpayers money to pay somebody to try and kill Colonel Gaddafi.

"I think it was a moral stand."

Football fan

Mr Shayler and his girlfriend Annie Machon, also a former member of the intelligence services both living in France. She was questioned for six and a half hours by Special Branch officers but was not prosecuted.

Mr Shayler admitted it had not been easy for his girlfriend but said: "We have a very close relationship and we discussed what was going to happen before it happened and we made that decision together."

Now Mr Shayler is hoping to publish a novel and is keen to return to Britain as soon as possible.

"Ideally obviously, I'd like to go back to the UK," he said. "It's the country where I grew up, my football team's there, I'd to be able to see them play football."

You can watch the HARDtalk interview in full on BBC World and News 24 at the times shown below.

BBC World (times shown in GMT)
February 24 1530 and 1930
Febraury 25 0730 and 0930