WASHINGTON (Reuters) – Attorney General Alberto Gonzales said on Sunday that he immediately told White House Chief of Staff Andrew Card — but delayed telling others — when the Justice Department launched an investigation into who leaked the identity of a CIA operative.

Gonzales, who at the time was White House counsel, told CBS”s &#34Face the Nation&#34 that he waited until the next morning to discuss the issue with President Bush and to formally notify the rest of the White House staff, requiring them to preserve any materials connected to the investigation.

Democratic Sen. Joseph Biden (news, bio, voting record) of Delaware said the approximately 12-hour delay in notification &#34raises a lot of questions&#34 about whether some White House officials could have received an early warning from Card.

&#34The real question now is, who did the chief of staff speak to? Did the chief of staff pick up the phone and call (Bush political adviser) Karl Rove? Did the chief of staff pick up the phone and call anybody else?&#34 Biden said.

Democrats have urged Bush to fire Rove or revoke his access to classified information after a reporter said he was a source about the identity of the CIA agent, Valerie Plame, in 2003. The leak came after Plame”s husband, former diplomat Joseph Wilson, accused the White House of twisting intelligence to justify the Iraq war.

It is against the law in some cases to knowingly reveal the identity of an undercover CIA officer.

A New York Times columnist reported on Sunday that Gonzales was notified about the investigation on the night of Sept. 29, 2003, but waited 12 hours before telling the White House staff about the inquiry.

Asked about the report on CBS, Gonzales said his office was notified about the investigation at about 8:00 p.m. and that he had his staff &#34go back to the Department of Justice lawyers and ask them, ”Do you want us to notify the staff now, immediately, or would it be OK to notify the staff early in the morning?&#34”

&#34And we were advised, go ahead and notify the staff early in the morning, that would be OK,&#34 Gonzales said. &#34Most of the staff had gone home. No one knew about the investigation.&#34

But Gonzales said he did tell one person at the White House — Card.

Gonzales said he told the president first thing the next morning, &#34and shortly thereafter, there was notification sent out to all the members of the White House staff.&#34

Biden said: &#34I don”t doubt the attorney general”s sincerity. But it does seem to me it wasn”t the soundest of judgments.&#34