FBI Director Robert Mueller testifies before a House panel Thursday.
WASHINGTON (CNN) - FBI Director Robert Mueller told Congress on Thursday that the confrontation in 2004 between then-White House Counsel Alberto Gonzales and then-Attorney General John Ashcroft in Ashcroft's hospital room was over the controversial warrantless surveillance program - in apparent contradiction of Gonzales' Senate testimony on Tuesday .
Mueller said he spoke with Ashcroft shortly after Gonzales left the hospital, and he was told the meeting dealt with "an NSA (National Security Agency) program that has been much discussed, yes."
Mueller made the comment as he testified before the House Judiciary Committee.
In testimony before the Senate Judiciary Committee on Tuesday, Gonzales insisted he had visited the ailing Ashcroft in the hospital to discuss "other intelligence activities," not the surveillance program.
Mueller also testified Thursday that he had serious reservations about the warrantless surveillance program at the time of the dramatic internal administration showdown and threats of top-level resignations.
Mueller did not confirm he had threatened to resign, but he twice said he supports the testimony of former Deputy Attorney General James Comey, who had testified that Gonzales and former White House Chief of Staff Andrew Card tried to pressure Ashcroft to reauthorize a surveillance program against terror suspects.
Mueller for the first time publicly confirmed he did dispatch - as Comey had testified - an FBI security detail to the hospital room to ensure that Comey was not removed from the room when Gonzales was there.
–CNN Justice Producer Terry Frieden