Watch the interview with the author of the article below.

Mohamed, 30, who returned to Britain last month from Guantanamo Bay after seven years detained without charge, said that he reached his lowest ebb the moment he realised that Britain was conniving in his torture.

'It was obvious the British were feeding them questions about people in London.

'It was when they started asking the questions supplied by the British that my situation worsened. They sold me out.'

Last month his lawyers persuaded the High Court not to allow parts of a judgement that summarised Mohamed's treatment to be published, on the grounds that to do so would jeopardise Britian’s intelligence-sharing relationship with America.

According to the documents, MI5 knew Mohamed had not been transferred to any known U.S. base, and did not know his whereabouts, but still fed the CIA questions in the knowledge that while he must be in some 'third country', he was ultimately under CIA control.

What was said at the conference remains unknown.

David Davis, the former Shadow Home Secretary, demanded that Mr Miliband make a fresh parliamentary statement on the case.

He said the officer knew he had already been tortured numerous times after his capture the previous month, with methods that included days of sleep deprivation, a mock execution and being beaten while being hung by his wrists for hours on end.

The strongest evidence of British collusion comes in the form of a confidential telegram sent from MI5 to the CIA on November 5, 2002.

It too has been heavily redacted but the surviving portion states: 'We note that we have also requested that briefs be put to Binyam Mohamed and would appreciate a guide from you as to the likely timescale for these too.

A spokesman said: 'The Attorney General is considering an allegation of criminal wrongdoing by British personnel.

Now read the full, exclusive interview

The worst time in Binyam Mohamed's seven-year ordeal in American captivity, worse even than the medieval tortures he endured for 18 months in Morocco, came in the first half of 2004 when he was held for five months at a secret CIA prison in Afghanistan.

'There were loudspeakers in the cell, pumping out what felt like about 160 watts, a deafening volume, non-stop, 24 hours a day.

'It's got about 20 songs on it and when it was finished it went back to the beginning and started again.

'Sometimes it was in a standing position, with my wrists chained to the top of the door frame.

'I couldn't sleep. I had no idea whether it was day or night.

'The water was salty and afterwards you felt dirtier than when you went in. It wasn't a shower for washing: it was for humiliation.'

'I said I had met Osama Bin Laden 30 times'

"'A hundred nights in Oscar Block is the equivalent of one night in the dark prison".

'In Kabul I lost my head. It felt like it was never going to end and that I had ceased to exist.'

Mohamed, 30, spoke to The Mail on Sunday at the house in the English countryside where he has been staying since he was flown to Britain from Guantanamo at the end of last month.

He revealed new details about MI5's alleged collusion in his torture, speaking for the first time about being interrogated in Pakistan by an MI5 officer who knew he had already been tortured numerous times after his capture, and how torture made him confess to a fantastical plot that never was - to build and detonate a 'dirty' radioactive bomb in New York.

Other sources have confirmed his record is accurate. He has made it available to The Mail on Sunday.

Since photos were taken of him emerging from the aircraft that brought him from Guantanamo, Mohamed has trimmed his beard and cut his hair.

But when he slips off his jacket, it is evident his frame is still skeletal.

He seems straightforward and makes no attempt to hide the chain of events that had led to his capture - including the training he received in an Afghan camp.

'Mentally right now, the result of my experience is that I feel emotionally dead.

Still fearful for his safety, Mohamed asked us to ensure he could not be recognised from the photograph published here.

'The British co-operated... they sold me out'

His odyssey began in 1992, when he was just 14.

He decided to flee, uprooting Mohamed and his elder brother and sister from the home in Addis Ababa where they had spent their childhood. He left behind his wife, Mohamed's mother.

However, Mohamed says he became a victim of racist bullying at his school.

'I didn't like the U.S. at all. It just didn't feel right for me to be there and I wanted to get out.'

The family had no connections in Britain, but because Mohamed spoke good English, his father decided to see if he could settle in London.

For about a week, Mohamed says, they stayed in a hotel. Then, although he was not quite 16, his father returned to America, leaving him vulnerable, without guidance or support.

Before he left, Mohamed's father told him to go to Social Services.

Meanwhile he applied for asylum and was given leave to remain.

'About two weeks later I smoked my first joint. It started from there.'

By 1998, Mohamed was regularly 'chasing the dragon' to smoke heroin and sometimes crack cocaine.

'I was also drinking a lot. Finally, I dropped out.'

Part of the answer turned out to be kick-boxing, and if he was searching for a father figure, he seems to have found it in his kick-boxing instructor, of whom he still speaks reverentially.

He says: 'I had to get fit again, and I started using my money to buy food again, not heroin.'

Although his mother was a Muslim, he had never practised any religion.

'I wanted to protect civilians, not kill them'

In the middle of 2000, he was offered a job as a mosque janitor and began to spend as much time there as he could, often staying the night - largely in order to avoid his old drug-abusing friends who still clustered around his apartment.

Mohamed says that someone at the mosque told him about the radical American civil rights leader Malcolm X, saying he had come to understand his religion properly when he went on a pilgrimage to Mecca.

Mohamed, he suggested, should go to see the 'pure' form of Islam being practised in Taliban-controlled Afghanistan.

How much did he know about what the Taliban stood for?

'Minus one,' Mohamed says. 'I really had no idea what it was.'

He had saved some money and flew to Islamabad, Pakistan's capital, in May 2001.

As an asylum-seeker, he couldn't apply for a new Ethiopian passport and had been unable to obtain a British travel document.

Instead, he borrowed a genuine British passport from a friend and substituted his own photograph.

After a week in Islamabad, Mohamed crossed the Afghan border by truck. It was, he says, easy: 'No one looked at my documents. I just kept down.'

Later, after the attacks of 9/11, the Americans who led the 'war on terror' assumed that because the Taliban had given refuge to Osama Bin Laden and Al Qaeda, the two were interchangeable, and that anyone who had the least involvement with the Taliban was a fully-fledged terrorist, bent - as former U.S. defence secretary Donald Rumsfeld said when he opened the Guantanamo prison in January 2002 - on 'killing millions of ordinary Americans'.

Mohamed insists that this was not the way he saw the world at all.

Back in London he had been moved and appalled by watching TV news stories about the plight of civilians caught in Russia's second war against Chechnya, where thousands, mainly Muslims, had been killed and tortured.

'To me, the Chechens were the freedom fighters and the Russians were the oppressors,' Mohamed says.

'It was the sight of the women and the kids being killed: innocent lives being lost for no reason.

'I wanted to go there to do what I could - not for fighting, but as an aid and rescue worker.'

At a guest house in Jalalabad, the first town in which he stayed in Afghanistan, he found people who had links with the Chechen resistance.

'I was told that the Russians don't separate between aid workers and those doing the fighting, and that if I wanted to go to Chechnya, I needed basic training.

'I was so young, I didn't question it. I didn't expect to fire a gun except in training, let alone kill someone.'

Mohamed adds: 'I would never have taken up arms against British or American soldiers, let alone attacked civilians.

'I wanted to protect civilians, not kill them.'

'They carried out a mock execution on me'

He underwent a 45-day boot camp course. Much of the time, Mohamed says, was spent sitting around doing nothing.

He even abandoned the course halfway through for a few days, before being persuaded that if he wanted to go to Chechnya he had to finish it.

He says he learnt nothing that could be construed as terrorist training: there were no lessons on bomb-making, for example.

Afterwards, Mohamed went to Kabul, where he contracted malaria. While he was recovering in hospital, news broke of 9/11.

It was evident the West was likely to attack Afghanistan, and Mohamed's immediate impulse was to leave.

'All I wanted to do was to get back to London, to the country that I thought of as home, to continue my education and find a job; to get back to my life, minus the drugs.'

As the U.S.-led coalition advanced, Mohamed became swept up in the tide of refugees.

He fled from city to city and in 2002 managed to cross into Pakistan and made his way to Karachi.

He booked a flight to London for April 3, but officials saw that his passport looked wrong and sent him packing.

Six days later, using the same document, he tried again. This time the Pakistanis detained him - and this was the start of almost seven years of incarceration without trial, interrogation and torture.

Two weeks after being detained, having been held in Landi prison, he met an American who called himself 'Chuck' and said he worked for the FBI.

Mohamed says: 'I told him I wanted a lawyer. He told me, "The law's changed. There are no lawyers.

"'Either you're going to answer me the easy way or I get the information I need another way."'

Senior U.S. officials in Washington say that in these early months after 9/11, American intelligence agencies were 'obsessed' with the possibility that Al Qaeda might have acquired nuclear fissile material.

'Every interrogator would ask questions about it,' one former CIA officer says. Thus it was that Mohamed unwittingly contributed to his fate.

As The Mail on Sunday revealed last month, his interrogation began to turn nasty after he mentioned that while he was in Pakistan he had seen a website with spoof instructions for building a nuclear device - instructions that included advice to refine bomb-grade uranium by whirling a bucket round one's head.

'I mentioned the website to Chuck,' Mohamed says.

'It was obviously a joke: it never crossed my mind that anyone would take it seriously.

'But that's when he started getting all excited.

'Towards the end of April he began telling me about this A-bomb I was supposed to be building, and he started on about Osama Bin Laden and his top lieutenants, showing me pictures and making out I must have known them.

'He started asking me about operations and what type I had been trained for.'

As the interrogations became more serious, the treatment meted out in the time between them brutally worsened.

Mohamed says: 'For at least ten days I was deprived of sleep.

'Sometimes the Pakistanis chained me from the top of the gate to the cell by my wrists from the end of one interrogation to the start of the next for about 22 hours.

'If I shouted, sometimes I would be allowed to use a toilet. Other times, they wouldn't let me go and I would p*** myself.

'They had a thick wooden stick, like a kind of paddle, which they used to beat me while I was chained.

'They'd beat me for a few minutes, then stop, then start again. They also carried out a mock execution.

'A guard put a gun to my head and said he was going to pull the trigger. They were saying, "This is what the Americans want us to do."'

Details of the abuse Mohamed underwent in Pakistan are contained in the 'redacted' section of the British High Court judgment on his case that Foreign Secretary David Miliband is refusing to release, claiming that to do so would damage the intelligence-sharing relationship with America.

As the court has made clear in the open section of its judgment, when an MI5 officer known as 'John' went to interrogate Mohamed on May 17, 2002, he was made fully aware of what had been happening.

'John was a white male, 30, with short black hair and a goatee,' Mohamed says.

'He was about 5ft 10in and stocky.

'There was another guy with him, about the same size with a full, dark beard. I don't know if he was British or American.

'The Americans had already been threatening to send me somewhere where I would be tortured far worse, like Jordan or Egypt.

'I was given a cup of tea and asked for one sugar. The other guy told me, "You'll need more than one sugar where you're going."

'They asked me about the A-bomb website and I told them it was a joke.

'They wanted to know everything about my life in the UK and I gave them all the information I had.

'Later I realised that was part of my undoing: I told them the area I lived in had 10,000 Moroccans and was known as Little Morocco.

'The feedback I got later from the Americans was that because the Brits told them I had lived in a Moroccan area, they thought Moroccans would be more likely to make me talk.

'At the same time, they thought I must know something about what Moroccans were up to in London.'

Mohamed says that a Moroccan interrogator who would deal with him later was even more specific.

'He told me, "Do you know who sent you here? The British sent you here."'

The materials seen by The Mail on Sunday confirm much of his account.

One MI5 memo from this period, disclosed to Mohamed via the American courts, suggests the British saw themselves as central to his interrogation.

It said: 'We believe that our knowledge of the UK scene may provide contextual background useful during any continuing interview process.

'This may enable individual officers to identify any inconsistencies during discussions.

'This will place the detainee under more direct pressure and would seem to be the most effective way of obtaining intelligence on Mohammed's [sic] activities/plans concerning the UK.'

Regarding the 'dirty bomb', MI5 could see the 'inconsistencies' in Mohamed's account. John dutifully recorded that he claimed the website was a joke.

But MI5 concluded that Mohamed and another prisoner being interrogated were 'lying to protect themselves' and 'evidently holding back'.

Day after day, MI5 kept the Americans supplied with questions and information.

Mohamed says: 'John told me that if I co-operated he'd tell the Americans to be more lenient with my treatment.'

In a further confidential memo John wrote: 'I told Mohammed [sic] that he had an opportunity to help us and help himself.

'The U.S. authorities will be deciding what to do with him and this would depend to a very large degree on his co-operation - I said that I could not and would not negotiate up-front, but if he persuaded me he was co-operating fully then (and only then) I would explore what could be done for him with my U.S. colleagues.'

Evidently, John felt he wasn't co-operating enough.

His memo concluded: 'While he appeared happy to answer any questions, he was holding back a great deal of information on who and what he knew in the UK and in Afghanistan.'

Mohamed was flown - trussed, gagged, blindfolded and wearing a giant nappy - from Islamabad to Rabat in Morocco on July 21, 2002.

He gave this date to Stafford Smith four years ago, it has since been confirmed by the CIA aircraft's flight logs.

Mohamed would not leave again for 18 months, for most of which he was horribly tortured.

Shuddering, he says the details of what he endured in Morocco are such that he cannot bring himself to relate them again.

But in 2005, when he first met Stafford Smith in Guantanamo, he dictated a detailed diary, which described the abuse that began at the beginning of September 2002.

He had, he said, already endured beatings at the hands of an interrogator named Marwan.

Now, he went on, 'they cut off my clothes with some kind of doctor's scalpel. I was totally naked. I was afraid to ask Marwan what would happen because it would show fear.

'I tried to put on a brave face. But maybe I was going to be raped. Maybe they'd electrocute me. Maybe castrate me.

'They took the scalpel to my right chest. It was only a small cut. Maybe an inch. Then they cut my left chest.

'One of them took my penis in his hand and began to make cuts. He did it once, and they stood still for maybe a minute, watching my reaction.

'I was in agony, crying, trying desperately to suppress myself, but I was screaming.

'I remember Marwan seemed to smoke half a cigarette, throw it down, and start another. They must have done this 20 to 30 times in maybe two hours.

'There was blood all over. They cut all over my private parts.

'One of them said it would be better just to cut it off, as I would only breed terrorists.'

This, Mohamed says, was repeated many times over the next 15 months.

Even after this treatment started, the documents disclosed to Mohamed for the U.S. court case reveal that MI5 was colluding with his tormentors.

In late September, one document reveals: 'The Service received a report from the U.S. of an interview of Mr Mohamed.

'On September 30, MI5 held a case conference about him with their American colleagues at MI5s London headquarters.

Weeks later, on November 5, came the strongest evidence to emerge of British collusion in Mohamed's illegal 'rendition' and torture, in the form of a telegram from MI5 to the CIA.

Headed 'Request for further Detainee questioning', it stated: 'This information has been communicated in confidence to the recipient government and shall not be released without the agreement of the British government.

'We would be grateful if the following can be passed to Binyam Mohamed.'

It went on to ask that his interrogators show him and ask him questions about a 'photobook recently sent over'.

Large portions of the telegram, which set out detailed questions, have been redacted, but it added: 'We would be grateful if the following could be put to Binyam Mohamed, in addition to the questioning above.

'Does Mohamed know [two lines redacted]? What was the man's name? How does Mohamed know him? Can Mohamed describe him? Where did they meet? Where was the man from?

'Who facilitated his travel from the UK? Where did this man go? What were his intentions?

'We would appreciate the opportunity to pose further questions, dependent on answers given to the above.'

A further telegram sent by MI5 on November 11 was headed 'update request'.

It, too, has been heavily redacted but the surviving portion states: 'We note that we have also requested that briefs be put to Binyam Mohamed and would appreciate a guide from you as to the likely timescale for these too.

'We fully appreciate that this can be a long-winded process, but the urgent nature of these enquiries will be obvious to you.'

Mohamed remembers very clearly the moment when MI5's questions were first channelled by his Moroccan interrogators.

He says: 'They started bringing British files to the interrogations - thick binders, some of them containing sheaves of photos of people who lived in London and places there like mosques.

'It was obvious the British were feeding them questions about people in London.

'When I realised that the British were co-operating with the people torturing me, I felt completely naked.

'It was when they started asking the questions supplied by the British that my situation worsened. They sold me out.'

Under this torture, Mohamed's confessions became ever more elaborate.

'They had fed me enough through their questions for me to make up what they wanted to hear. I confessed to it all.

'There was the plot to build a dirty nuclear bomb, and another to blow up apartments in New York with their gas pipes.'

This - supposedly the brainchild of the 9/11 planner Khalid Shaikh Mohammed - always sounded improbable: it was never quite clear how gas pipes might become weapons.

'I said Khalid Shaikh Mohammed had given me a false passport after I was stopped the first time in Karachi and that I had met Osama Bin Laden 30 times. None of it was true.

'The British could have stopped the torture because they knew I had tried to use the same passport at Karachi both times.

'That should have told them that what I was saying under torture wasn't true. But so far as I know, they did nothing.'

Mohamed was finally 'rendered' by the CIA again in January 2004 and taken to Afghanistan. He says the agents he met there responded with horror.

'When I got to Kabul a female agent started taking close-up pictures of my genitals. She was shocked.

'When they removed my diaper she could see blood was still oozing from the cuts on my penis.

'For the first two weeks they had me on antibiotics and they took pictures of my genitals every day.

'They told me, "This is not for us. It's for Washington." They wanted to be sure it was healing.'

Then came his ordeal in the dark prison. Mohamed says the thrust of his interrogations had changed.

Since he madehis fantastical confession, the Americans wanted him to become a prosecution witness in their system of special military commissions, against Al Qaeda bigwigs he had never met.

He reached Guantanamo in September 2004.

There, the interrogations continued but there had been another shift.

He says: 'They said they were worried I would tell the court that I had only confessed through torture. They said now they needed me to say it freely.

'We called them the clean team, they wanted to say they had got this stuff from a clean interrogation.'

After Mohamed had spent more than four years at Guantanamo, Barack Obama became U.S. President and announced the camp's impending closure and an end to the military commissions.

But according to Mohamed, there was little sign of an improvement.

'Since the election it's got harsher. The guards would say, yes, this place is going to close down, but it was like they wanted to take their last revenge.'

The feared Emergency Reaction Force, a SWAT team used to punish inmates in their cells, is being used more often, he says.

Mohamed recalls an occasion when it was deployed against him.

The reason was that he was refusing to give his fingerprints which, despite all the torture, had unaccountably not been taken before: he says he feared they might use them to frame him.

'They nearly broke my back. The guy on top was twisting me one way, the guys on my legs the other.

'They marched me out of the cell to the fingerprint room, still cuffed. I clenched my fists behind me so they couldn't take prints, so they tried to take them by force.

'The guy at my head sticks his fingers up my nose and wrenches my head back, jerking it around by the nostrils.

'Then he put his fingers in my eyes. It felt as if he was trying to gouge them out.

Another guy was punching my ribs and another was squeezing my testicles. Finally I couldn't take it any more. I let them take the prints.'

Last October, before the election, all charges against him were dropped, even the Americans had come to realise there was no 'dirty bomb' plot.

Yet to Mohamed, it seemed he was no closer to release - hence his decision, on December 29 last year, to go on hunger strike.

Release, when it finally came last month, took him by surprise. It is, he admits, still difficult to accept.

'I kept being told, you'll be free in ten days, and they would pass, and then I'd be told another ten days, and still it wasn't for real.'

As for the future, he is determined to stay in Britain, despite MI5's alleged collusion with his torturers.

'It's the only place I can call home,' he says. 'I want to live a normal life, to find a wife, get married, have a family, a job.

'Meanwhile, I'll do whatever I can to get the other innocent prisoners out of Guantanamo.'

* The Mail on Sunday has made no payment to Binyam Mohamed. We will be making a donation to the Helen Bamber Foundation.