PRESS ASSOCIATION -- A Libyan rebel commander has claimed UK intelligence agents knew he was being tortured but did nothing to help him.

Abdul Hakim Belhadj said he clearly signalled his physical abuse during an interview in Tripoli but nothing was done to stop the violence against him.

Belhadj is threatening to sue the British Government for its alleged involvement in his 2004 rendition and subsequent imprisonment.

Documents uncovered by Human Rights Watch in the offices of Libyan dictator Muammar Gaddafi's former security chief Musa Kusa suggested that the UK was involved in helping Libya detain terror suspects including Belhadj.

Belhadj told The Times that during a meeting with three British agents he made chopping motions with his hands to signal his treatment.

He said "they moved their heads and agreed... they got my message" and added that "I have no doubt, not a single doubt, they knew", but the torture continued.

Belhadj claimed he was locked in solitary confinement, hung up, beaten and denied a shower for three years.

According to one of the documents found by Human Rights Watch MI6 dispatched an intelligence officer to Tripoli after Belhadj's detention to obtain information of "urgent importance" from him relating to UK anti-terrorist operations.

An independent inquiry is to look into claims that the UK traded information with Gaddafi's security forces in return for intelligence extracted from detainees in the country's jails.

Prime Minister David Cameron told MPs that the allegations were "significant" and would be examined "very carefully" by Sir Peter Gibson's inquiry, which was set up last year to consider allegations of UK complicity in the mistreatment of terror suspects in Guantanamo Bay.