CIA Director John Brennan has defended his agency's record after a Senate report exposed "brutal" torture of terror suspects.

The career officer admitted some colleagues had committed "abhorrent" acts in the tense and difficult years after the September 11 attacks.

But he insisted the Bush-era CIA had done more good than evil and that tortured detainees had helped provide information that helped America find and kill Al Qaida leader Osama Bin Laden.

Mr Brennan said: "There were no easy answers, and whatever your views are on enhanced interrogation techniques, our nation and in particular this agency did a lot of things right during this difficult time to keep this country strong and secured."

Speaking at a rare press conference at the CIA HQ outside Washington in Langley, Virginia, he admitted that before 9/11 his agency had little experience of detaining and interrogating prisoners.

He said: "The CIA was unprepared to conduct a detention and interrogation program, and our officers inadequately developed and monitored its initial activities."

Mr Brennan acknowledged that his agency had made mistakes after it was ordered to track down terrorists by former President George Bush. He declined to characterise so-called "enhanced interrogation techniques" or EITs as torture but said he supported the decision of current President Barack Obama to ban them.

The programme lasted from 2001, when Mr Brennan was a senior officer, to 2007 and has been the subject of major international concern ever since.

However, Mr Brennan disputed the conclusion of the Senate that the CIA had misled the public that torture had led to information that thwarted terror attacks, including in the UK.

He said detainees subjected to EITs had given valuable information but that it was unknowable if they would have done so had they not been subjected to the techniques.

He said: "It our our view that the detainees who were subjected to EITs provided information that was used in the ultimate operation against Bin Laden.

"I am not going to attribute that to the use of the EITs. "

The Senate report concluded that torture was simply ineffective.

Mr Brennan suggested "exaggeration" of CIA actions in the international press was damaging the agencies work with overseas partners.

He said: "There is a lot of hyperbole that is fuelling the debate and is harmful to the continued our intelligence cooperation."

The director, who is facing calls to resign from at least one Democrat senator, fielded questions from the press in a live on-the-record briefing.

Scottish and other international law enforcement agencies are now undnerstood to be seeking more details of the Senate report, which was only a summary of its investigation.

Mr Brennan suggested he would not like to see more information put in to the public domain.

He said: "I think there's been more than enough transparency that's happened over the last couple days. I think it's over the top."

Meanwhile, Downing Street has admitted that UK intelligence agencies discussed making redactions to the Senate report with their American counterparts.

The 500-age summary did not include references to any British agency or to so-called torture flights using Scottish or other UK airports.

A spokeswoman for Prime Minister David Cameron said: "My understanding is no redactions were sought to remove any suggestion that there was UK involvement in any alleged torture or rendition.

"Any redactions sought there were done on national security grounds in a way we would have done with any other report."