Former President George Bush's claims that "waterboarding" garnered valuable intelligence that saved lives have been disputed in the UK.
Lord MacDonald, former Director of Public Prosecutions, said:
"These stories about waterboarding thwarting attacks on Canary Wharf and Heathrow - I've never seen anything to substantiate these claims.
These claims are to be treated with a great deal of scepticism."
Legal experts are also of the view that, having sanctioned the interrogation technique, Bush could be arrested for breaking international law if he travels abroad.