The first British Guantanamo Bay inmate to sell his story claimed last night that inmates were given repeated punishment beatings and chained in irons for hours on end.

Jamal al-Harith, 37, a divorced father-of-three from Manchester, said that detainees were shackled with leg cuffs with metal links that cut into the skin.

He claims to have been questioned 40 times by FBI, CIA and MI5 agents and said that while he was interrogated he was bolted to the floor for up to 12 hours at a time.

As punishment in the camp, inmates were forced to lie in a ball for hours, he said.

"Sometimes you would be chained up on the floor with your hands and feet actually bound together. One of my friends told me he was kept like that for 15 hours once," Mr al-Harith told the Daily Mirror.

Mr al-Harith claimed the water served to inmates was foul - yellow in Camp X-ray and black in Camp Delta - and that the diet was rice and beans.

"They would shut off the water before prayers so we couldn't wash ourselves according to our religion," he said.

"They would play tricks on people by denying them things - you might be the only person on your block who didn't get any bread.

"They actually said 'You have no rights here'.

"After a while we stopped asking for human rights - we wanted animal rights."

He went on: "You would be punished for anything - for having six packets of salt in your cell rather than five, for hanging your towel through the cage if it wasn't wet, even for having your spoon and things lined up in the wrong order."

He said inmates were forced to use a bucket as a toilet in view of other inmates and guards.