The UN has expressed concern at the government's decision to hand an independent inquiry into the UK's awareness of torture in foreign jails over to MPs.
An interim report by former judge Sir Peter Gibson, which was released last week, found that British intelligence officials were aware of the mistreatment of detainees.
But Cabinet minister Ken Clarke announced that the investigation would be taken up by the parliamentary Intelligence and Security Committee (ISC).
UN Special Rapporteur on torture Juan E. Méndez said:
A senior Conservative MP has said "it is truly shocking" that Britain helped the United States to kidnap and torture British detainees, as he warned that the Government would come to regret its decision not to allow an independent judge-led inquiry to run its course.
Andrew Tyrie said today's confirmation by Cabinet Office minister Ken Clarke that the investigation would instead be handed over to Parliament's controversial Intelligence and Security Committee (ISC) was "a mistake".
Cabinet Office minister Ken Clarke said the report into the treatment of detainees "paints a picture" of Government and agencies struggling to adapt to the new realities faced in the wake of 9/11 and said it was a matter of "sincere regret" if "mistakes and failures were made".
A committee of MPs is to examine the 27 different areas of concern highlighted by the initial stages of a scrapped inquiry into rendition and torture, the Government said.
Ken Clarke told MPs the initial findings of Sir Peter Gibson's inquiry would be passed to the Intelligence and Security Committee, with a view to a report coming back at the end of next year.
The Gibson report acknowledges the "extreme harshness" of the conditions and treatment of detainees in the so-called war on terror and it calls into question the conduct of British intelligence officers.
There is no evidence that UK intelligence officers were directly responsible for the mistreatment of detainees.
It does say British intelligence officers were aware of mistreatment but that "in some instances officers did not recognise or report treatment issues, which fell short of torture".
It also says British intelligence officers warned detainees they might face "negative consequences" if they did not cooperate.
The detainees took these kind of warnings as a threat.
Sir Peter Gibson said it was not always clear that government ministers were kept informed of mistreatment issues and he says the UK may not have known the full extent of the US secret rendition programme which moved detainees around the world.
There is evidence that UK intelligence officers were aware of inappropriate interrogation techniques and mistreatment of some detainees held in other countries, a new report has found.
Revealing the findings of the detainee inquiry in the House of Commons, Cabinet minister Ken Clarke said the report identified 27 issues requiring further investigation.
The inquiry was set up by David Cameron in 2010 to investigate whether Britain was implicated in the improper treatment of detainees held by other countries in the aftermath of the 9/11 terrorist attacks.
There was also evidence that the Government or its agencies may have become "inappropriately involved" in some cases of rendition.
Mr Clarke said allegations of illegal rendition have harmed the reputation of the UK and its security services.
The inquiry examined more than 20,000 documents with the majority highly classified material.
Sami al Saadi, the Libyan dissident who the Government has agreed to pay over his rendition, says he still doesn't know the truth. He said:
The Government has agreed to pay more than £2 million to the family of a Libyan dissident after accepting its role in his illegal rendition, his legal team said today.
Sami al Saadi, a leading Gaddafi opponent, was imprisoned and tortured after he was forced to board a plane back to Tripoli along with his wife and four children in 2004.
Ministers are now understood to have offered him a sum of £2.2 million for its role in the joint UK-US-Libyan operation, but the Government has not admitted liability, Mr al Saadi said.
Jack Straw has said he cannot comment on the claims by Abdel Hakim Belhadj that the MP was involved in his rendition.
Cori Crider, the legal director of Reprieve, said the public had the right to know how and why the government became complicit in the rendition of families, including children and a pregnant women, to Libya.