WASHINGTON (AP) – CIA Director Porter Goss said Thursday that the disclosure of President Bush’s eavesdropping-without-warrants program and other once-secret projects had undermined U.S. intelligence-gathering abilities.

“The damage has been very severe to our capabilities to carry out our mission,” Goss told the Senate Intelligence Committee. He said a federal grand jury should be empaneled to determine “who is leaking this information.”

His testimony came after National Intelligence Director John Negroponte, who directs all intelligence activities, strongly defended the program, calling it crucial for protecting the nation against its most menacing threat.

“This was not about domestic surveillance,” Negroponte said.

Leaders of the nation’s intelligence agencies appeared before the panel in a rare public session to give a rundown on threats facing the world.

Negroponte called al-Qaida and associated terror groups the “top concern” of the U.S. intelligence community, followed closely by the nuclear activities of Iran and North Korea.

Committee Democrats sought to change the focus to the president’s decision to authorize the National Security Agency to eavesdrop _ without first obtaining warrants _ on communications to and from those in the United States and terror suspects abroad.

“The president has not only confirmed the existence of the program, he has spoken at length about it repeatedly,” while keeping Congress in the dark, said Sen. Jay Rockefeller of West Virginia, the panel’s senior Democrat.

“The administration wants to have it both ways,” said Sen. Carl Levin, D-Mich.

Goss complained that leaks to the news media about the surveillance program and activities such as reported CIA secret prisons abroad had damaged his own agency’s work.

“I use the words `very severe’ intentionally. And I think the evidence will show that,” Goss said.

He said not only have these revelations made it harder for the CIA to gather information, but they have made intelligence agencies in other countries mistrustful of their U.S. counterparts.

“I’m stunned to the quick when I get questions from my professional counterparts saying, `Mr. Goss, can’t you Americans keep a secret?'” he said.

Goss cited a “disruption to our plans, things that we have under way.” Some CIA sources and “assets” had been rendered “no longer viable or usable, or less effective by a large degree,” he said.

“I also believe that there has been an erosion of the culture of secrecy and we’re trying to reinstall that,” Goss said.

“I’ve called in the FBI, the Department of Justice. It is my aim and it is my hope that we will witness a grand jury investigation with reporters present, being asked to reveal who is leaking this information,” he said.

Rockefeller suggested that the “leaks” Goss talked about most likely “came from the executive branch” of the government.

That brought a terse response from FBI Director Robert Mueller, who said, “It’s not fair to point a finger as to the responsibility of the leak.”