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

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 PM, who sat in No 10 from 1997 to 2007, said co-operation with Libya 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 Gaddafi's regime last year.

Asked yesterday about the incident, and whether similar examples lay behind distrust of the West, Mr Blair said: "About the Belhadj case, I don't have any recollection of it at all. There are many complicated reasons why the West's relationship is difficult with the Middle East but I think [rendition] is the least of them.

"Rendition has been the policy of successive US administrations. It remains the policy of this US. 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 China, says he was tortured after being detained with his wife in 2004 en route to the UK to seek asylum.

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

Sir Mark is named in the pair's legal action, alongside the Government, and the Commissioner's office in the British Indian Ocean Territory of Diego Garcia – through where they allege the rendition transferred.

But Mr Blair defended the relationship with Libya and the role intelligence agencies play in defending Britain from external threats.

He said: "Our co-operation in the fight against terrorism was important. Make no mistake about that."