Abdel Hakim Belhadj is suing the UK government

Tony Blair said today he has no memory of the Belhadj rendition case but claimed he was not aware of any occasion when his government breached its opposition to the tactic.

Speaking to the BBC Radio 4's The World At One programme, Mr Blair defended the security services as doing an important, dangerous job, one which he said generally deserves the "full support of the country".

The former prime minister, who sat in No 10 from 1997 to 2007, said cooperation with the former Libyan regime against terrorism had been "important".

Libyans Sami Al Saadi and Abdel Hakim Belhadj are suing the British Government for what they claim is its complicity in their alleged rendition and torture in 2004 after several documents emerged in the wake of the fall of Colonel Muammar Gaddafi's regime last year.

Asked about the incident, and whether similar examples lay behind distrust of the West, Blair said: "About the Belhadj case, I don't have any recollection of it at all.

"There are many, many complicated reasons why the West's relationship is difficult with the Middle East but I think (rendition) is probably the least of them.

"Rendition has been the policy of successive US administrations. It remains the policy of this US administration.

"We have always had our own position. Jack Straw made it very clear at the time and as far as I know, we absolutely adhered to that position."

Also known as Abu Abd Allah Sadiq, Mr Belhadj, 45, a Libyan rebel commander who was living in exile in Beijing, China, says he was tortured after being detained with his wife in 2004 en route to the UK where they were trying to seek asylum.

The civil action stems from the discovery of a letter purportedly from Sir Mark Allen, the former MI6 director of counter terrorism, to Moussa Koussa, head of Gaddafi's intelligence agency, dated 18 March 2004.

In it, Sir Mark is said to pass on thanks for helping to arrange Tony Blair's visit to Gaddafi, writing: "Most importantly, I congratulate you on the safe arrival of Abu Abd Allah Sadiq.

"This was the least we could do for you and for Libya to demonstrate the remarkable relationship we have built over the years."

Sir Mark is named in the pair's legal action, alongside the Government, as is the Commissioner's office in the British Indian Ocean Territory of Diego Garcia - a location through which they allege the rendition transferred.

But Blair defended the relationship with Libya at the time and the role intelligence agencies play in defending Britain against external threats.

He told the programme: "In respect of Libya, don't be under any doubt at all - and this is quite apart from the Belhadj case, I can't comment because I simply don't know the details of it.

"But our cooperation with them in the fight against terrorism was important. Don't be under any mistake about that.

"This is about our security services. These are people who do a very difficult job, protecting our country in very difficult circumstances.

"I'm sure this matter will be investigated, as it should be, but don't forget that.

"These are people who often put their own lives on the line trying to protect our country. Every so often we should be aware of that and they should know that, in general terms - and I'm not talking about any specific case - they have the full support of the country in doing so."