The head of MI6 said today there was "no torture and no complicity in torture" by the British secret service.
Speaking to the BBC, Sir John Scarlett said: "Our officers are as committed to the values and the human rights values of liberal democracy as anybody else."
His comments came as the Government faced mounting calls for an independent inquiry into possible British complicity in overseas torture, despite a public assurance by two of the most senior Cabinet ministers on the issue.
Foreign Secretary David Miliband and Home Secretary Alan Johnson spoke out as a second influential parliamentary committee expressed concerns that the UK could be in breach of legal obligations by regularly using information from suspect sources.
Speaking on BBC Radio 4's programme MI6: A Century in Shadows, Sir John defended the actions of the Secret Intelligence Service, better known as MI6.
He said: "(Our officers) have the responsibility of protecting the country against terrorism and these issues need to be debated and understood in that context."
He also stressed that British intelligence services had not been compromised by close relationships with similar services in the US.
"Our American allies know that we are our own service, that we are here to work for the British interests and the United Kingdom," Sir John said.
"We're an independent service working to our own laws - nobody else's - and to our own values."
Mr Miliband and Mr Johnson used a Sunday newspaper article to insist every effort was made to ensure intelligence gained from terror suspects held abroad was not obtained through torture.
But they said there could be no 100% guarantee that such methods were not used, claiming tough judgments had to be made between the possibility and the need to protect the UK from attack.
Amnesty International dismissed their statements as "excuses" as campaigners, politicians and Muslim groups all joined the demands for an official inquiry.
The Foreign Affairs Committee expressed concern about Britain's relationship with Pakistan's Inter-Services Intelligence (ISI) agency, asking what steps had been taken to investigate claims of torture by human rights groups and why the Government considered them "baseless".
Its hard-hitting report came hot on the heels of another by the Joint Committee on Human Rights which said an independent inquiry was the only way to restore public confidence in the intelligence and security agencies.
There have been a string of allegations about the involvement of UK intelligence agencies in the questioning of terrorist suspects abroad, including supplying questions for interrogators to ask.
Scotland Yard is conducting a criminal investigation into claims that MI5 was complicit in the abuse of Binyam Mohamed, a British resident who alleges that he was tortured while being held at sites in Pakistan, Morocco and Afghanistan.
The Cabinet ministers, writing in The Sunday Telegraph, said there was no policy "to collude in, solicit, or directly participate in abuses of prisoners" or to cover up alleged wrongdoing.
"Our agencies are required to seek to minimise, and where possible avoid, the risk of mistreatment. But it is not possible to eradicate all risk. Judgments need to be made."
A spokesman for Amnesty said: "Any hint that the UK may be content to accept information that may be fresh from the torture chamber is very dangerous.
"It may be taken as tacit acceptance of torture and give a green light for the infliction of yet more pain and torture.
"Britain should stand firm in its opposition to torture both through our words and our actions.
"We have had weeks of bland denials of UK complicity. Now we've got excuses and what we need, as soon as possible, is a full independent inquiry."
The Liberal Democrats and the Scottish National Party have both appealed for an inquiry while the Tories have not ruled one out but say police investigations must take priority.
Shadow foreign secretary William Hague said ministers needed to answer MPs' questions more fully, publish guidance to security and intelligence staff and hold "a more thorough investigation into the allegations that have been made".
"These are the sorts of things that need doing in order to reassure the world that we really mean it when we say we do not collude in torture, we are not complicit in torture in any way," he said.
Shami Chakrabarti, director of campaign group Liberty, said: "The carefully crafted article is most revealing for what it doesn't say.
"Did Ministers authorise systematic arrangements that contributed to torture abroad? Were MI5 officers told to look the other way and let foreign powers do our dirty work?
"Only an independent judicial inquiry will answer these questions and allow Britain's security services to move on."
Mohammed Shafiq, chief executive of Muslim youth group the Ramadhan Foundation, added: "Only a public inquiry now will restore trust.
"If they continue to refuse this request the British people will draw their own conclusions that their Government has been complicit in torture."
Kim Howells, Labour chairman of the Intelligence and Security Committee which scrutinises the secret services, said the issue of UK complicity in torture had been "clarified as far as it can be on the evidence that we have".
"I can tell you that we've found no evidence that there has been collusion between the intelligence services, any Government department and governments that torture their individuals," Mr Howells told the BBC Radio 4 Today programme.
"My committee has been looking at this for a very long time now and we have never been denied evidence from any of the agencies, nor the Cabinet Office, nor any official in any Government department.
"So I'm very worried that these calls for judicial inquiries and so on are really treating the intelligence agencies as guilty until proven innocent and that's very, very dangerous for the security of this country."
Mr Howells said "no government on Earth" could guarantee that prisoners who had been picked up and held in another country had not had their human rights abused in some way.
But, he added: "If we don't have that information from other intelligence agencies, how can you be sure that there aren't jihadists who are trying to murder citizens on the street or Irish republicans who want to blow people to pieces in order to further their cause? You have no way of knowing that."
Tory MP David Davis, who campaigns on civil liberties issues, questioned Mr Howells' assurances.
"Only last week the Government had to apologise to the court for withholding documents in the Binyam Mohamed case and had to admit that one of the intelligence officers had misled the court," he said.
"If even the courts are misled, what hope has the Government's own committee?"
He said that ministers needed to state explicitly whether intelligence officers had been complicit in torture in terms of enabling or encouraging arrests by agencies known to use torture, supplying questions or back-up intelligence, or interviewing suspects after or between torture sessions.
"Any of these amounts to complicity and the Government has yet to deny one of them," he said.
Downing Street rejected calls for an inquiry into the claims of UK complicity in torture.
A No 10 spokesman said the Government had already said it would publish the guidance it issues on the interrogation of detainees held abroad once it has been revised.
"We do not support calls for an inquiry," the spokesman said. "We believe that an inquiry is not necessary."Reuse content