A Libyan man suing the British government for its alleged role in his 2004 rendition to Libya has offered to settle the case.
Abdul Hakim Belhaj is also suing former Foreign Secretary Jack Straw and ex-senior MI6 official Sir Mark Allen.
Mr Belhaj says he wants an apology, an admission of liability and a token payment of £1 from each.
The government said it is co-operating with investigations into UK involvement in ex-Libyan detainees' mistreatment.
Mr Belhaj is a former member of an Islamist insurgent group which sought to overthrow Col Muammar Gaddafi in the 1990s. He was also a key brigade leader in the 2011 toppling of the Libyan dictator, working with Nato.
His offer comes as MPs are due again to debate controversial legislation that would take cases like Mr Belhaj's behind closed doors.
Mr Belhaj, who began legal action last year, says he and his wife were detained by US intelligence officers at Bangkok Airport in March 2004.
He was allegedly tortured for several days while his wife Fatima Bouchar, who was five months' pregnant, was chained to a wall at a secret prison at the airport.
He believes he was rendered from Bangkok to Libya by the CIA and the flight refuelled on the island of Diego Garcia, the British overseas territory in the Indian Ocean.
He says his rendition - the act of transferring people from one jurisdiction to another - was approved by the UK government and British intelligence was responsible for a tip-off that led to his capture.
When he arrived in Tripoli, he says he was locked up for more than four years in the notorious Abu Saleem prison where he was interrogated and tortured.
Mr Belhaj has now written to those he is suing, saying he wants to lay to rest the misconception that he is pursuing the case to enrich himself.
In a letter sent to Prime Minister David Cameron, Mr Straw, and Sir Mark, Mr Belhaj said: "I am making an open offer to settle our litigation.
"My wife and I are willing to end our case against the UK government and Messrs Straw and Allen in exchange for a token compensation of a British pound from each defendant, an apology and an admission of liability for what was done to us."
A government spokesman said: "We can confirm we have received a letter from Mr Belhaj.
"Her Majesty's Government is co-operating fully with investigations into allegations made by former Libyan detainees about UK involvement in their mistreatment by the Gaddafi regime.
"A police investigation is under way so we are unable to comment further."
Another claimant with a similar case, Sami Al-Saadi, dropped his legal action in December in return for a payment of more than £2m.
The BBC's security correspondent Gordon Corera said: "This week the Security and Justice Bill returns to the House of Commons which would introduce secret hearings for civil cases such as this.
"Mr Belhaj says he has seen the government justifying the bill on the basis of avoiding large payouts and he says his case could be settled at little cost to the taxpayer."