Former US deputy Secretary of State Richard Armitage has acknowledged being the original source in the leak of a CIA official's identity.
"It was a terrible error on my part," Mr Armitage told the New York Times.
"There wasn't a day when I didn't feel like I had let down the president, the secretary of state, my colleagues, my family and the Wilsons. I value my ability to keep state secrets. This was bad and I really felt badly about this."
Mr Armitage was the first person to discuss the identity of former CIA official Valerie Plame with reporters after her husband, former Ambassador Joseph Wilson, criticised the Bush administration's Iraq policy in a New York Timesopinion piece.
Knowingly disclosing the identity of a covert CIA agent is against the law, but no officials have been charged with leaking Ms Plame's identity to the news media in 2003.
Former vice presidential aide Lewis "Scooter" Libby has been charged with lying to investigators as they sought to find out who leaked Mr Plame's identity.
Mr Armitage is expected to be a witness at his perjury trial, according to a court motion by the defence.
He said he wanted to disclose his role in the leak as soon as he realised he was the main source for a Robert Novak column which named Ms Plame as a CIA intelligence officer, the newspaper reported.
But he said he kept quiet at the request of Patrick Fitzgerald, the prosecutor investigating the leak.
Mr Armitage also confirmed he was the anonymous government official who told Washington Postreporter Bob Woodward about Ms Plame's identity before other Bush administration officials mentioned her name to reporters, the newspaper reported.
In an interview on CBS television, Mr Armitage said that as soon as he realised what he'd done he told FBI investigators it was an inadvertent leak. He said he did not hire a lawyer.