UPDATE: Here are relevant quotes from WarandPiece.com:
Update II: Reader SS sends these quotes along:
"I don't know of anybody in my administration who leaked classified information. If somebody did leak classified information, I'd like to know it, and we'll take the appropriate action." [Bush Remarks: Chicago, Illinois, 9/30/03]
"The President has set high standards, the highest of standards for people in his administration. He's made it very clear to people in his administration that he expects them to adhere to the highest standards of conduct. If anyone in this administration was involved in it, they would no longer be in this administration." [White House Briefing, 9/29/03]
Uh huh.