US:Michael Mukasey, President George Bush's nominee as US attorney general, faced a growing prospect of rejection by the senate after he told senators that he could not say if "waterboarding", a form of simulated drowning allegedly used by CIA interrogators, was illegal.
In a letter to the senate judiciary committee, Mr Mukasey said he considered interrogation methods such as waterboarding "repugnant" but he added that he had not been briefed on CIA interrogation techniques and could not base a legal opinion on "hypothetical facts and circumstances".
A former federal judge, Mr Mukasey said that, if he is confirmed as attorney general, he will review any coercive interrogation techniques used by US personnel to ensure that they are within the law.
"If, after such a review, I determine that any technique is unlawful, I will not hesitate to so advise the president and will rescind or correct any legal opinion of the department of justice that supports use of the technique," he said.
Mr Mukasey's letter did little to calm Democratic concerns about his attitude to torture and the four senators seeking the Democratic presidential nomination said they would oppose his confirmation.
Front-runner for the Democratic nomination Hilary Clinton said: "There is an easy way for Mukasey to get around the fact that he has not been briefed on what the CIA did: just define waterboarding, say whether waterboarding so defined is torture, and add that not having been briefed on what the CIA did, he doesn't know whether or not what they did meets his definition.
"That Mukasey has not taken this obvious route suggests that he is not motivated by his own uncertainty, but by the desire to keep people he believes have engaged in torture from being punished for their crimes."
The senate judiciary committee will vote on Mr Mukasey's nomination next week.