WASHINGTON (CNN) -- President Bush has settled on Air Force Gen. Michael Hayden as his choice for CIA director, and an announcement is planned for Monday, senior administration officials told CNN late Friday.

Hayden, 61, is the principal deputy to National Intelligence Director John Negroponte.

If confirmed by the Senate, Hayden would replace Porter Goss, who abruptly resigned the CIA post earlier Friday after losing what intelligence sources described as a power struggle with Negroponte.

Hayden was director of the National Security Agency in 2001 when Bush authorized a controversial program allowing the agency to monitor the communications of people inside the United States who were in contact with suspected terrorists overseas without first obtaining a warrant.

Critics charge the surveillance program is a violation of law and an assault on civil liberties. Hayden has defended the program, insisting that it is a necessary tool to thwart terrorists and that the process of obtaining warrants is too slow and cumbersome to deal with "a lethal enemy."

Intelligence sources told CNN that Goss' resignation was triggered by differences with Negroponte over plans to move staff, including analysts from the CIA's counterterrorism center, to other intelligence agencies.

Goss was worried about too many people being taken out of key roles, the sources said. (TIME.com: The Incredible Shrinking CIAexternal link)

Also, requests for information by Negroponte's office, which was created in December 2004 to oversee all U.S. intelligence efforts, were overtaxing CIA employees to the point that their work was being interfered with, the intelligence sources said.

"There's been a steady encroachment on what we do," one intelligence official said, and Goss felt he needed to resign rather than accept it.

'Mutual understanding'

An intelligence source with detailed knowledge of the discussions surrounding Goss' departure told CNN that after Goss resisted the changes, Negroponte sought White House backing to resolve the impasse.

A mutual decision was then made that Goss should go, and Hayden was involved in those discussions, the source said.

A senior administration official said Goss' resignation was based on a "mutual understanding" between Bush, Goss and Negroponte.

"When you ask somebody to do very difficult things during a period of transition, it often makes sense to hand off the reins to somebody else to take the agency forward," the senior administration official said.

An intelligence official told CNN that while there were differences of opinion between Goss and Negroponte, suggestions of any harsh exchanges between the two men were "just ridiculous, not remotely true."

In April, a senior administration official told CNN that Goss would likely be out of the CIA post before the end of the summer.

Goss and other senior intelligence officials have recently been interviewed by the president's Foreign Intelligence Advisory Board, which is looking into concerns that change was happening too slowly at the CIA.

Goss said he would remain at the helm of the CIA for the "next few weeks" to oversee the transition to a new director.

Former critic led shake-up

Goss, 67, a former CIA officer and Republican congressman from Florida, was tapped by Bush in June 2004 to come in and shake up the agency at a time when its performance was under intense scrutiny due to intelligence failures prior to the September 11, 2001, terrorist attacks and the invasion of Iraq.

Some of the most blistering criticism came in a report from the House Intelligence Committee -- which Goss then chaired -- that called the CIA "dysfunctional."

But two months after Goss was nominated, Bush asked Congress to implement a recommendation from the 9/11 commission to create an overall national intelligence director, which would oversee the CIA and 14 other intelligence agencies -- a change that diluted the authority of the CIA director.

Negroponte, the former U.S. ambassador to Iraq, was confirmed as national intelligence director in April 2005. After the restructuring, Bush began receiving his daily intelligence briefings from Negroponte rather than Goss.

Goss made good on his promise to shake up the CIA, bringing in his own management team to implement changes. A number of top CIA officials left during the transition, after personality and policy clashes with Goss' lieutenants.

However, in October, the White House decided to make Goss the manager of all U.S. human intelligence-gathering operations, which was widely seen as a way to restore some of the prestige the CIA lost after Congress created the post of national intelligence director. (Full story)

Former intelligence officials told CNN that many people inside the CIA are "relieved" that Goss and his aides -- called "the Gosslings" by CIA insiders -- are going, a reflection of the ill will that still persists over the earlier departures of senior officials.

'Bizarrely sudden'

Goss' abrupt resignation Friday took Washington by surprise. Reporters were summoned in early afternoon to the Oval Office, where Bush -- with the CIA director seated next to him -- announced the change.

No reason was given for Goss' resignation, but the White House has been in the midst of an administration shakeup since Josh Bolten took over as chief of staff.

"[Goss] offered his resignation as the director of the Central Intelligence Agency. I've accepted it," Bush said.

"Porter's tenure at the CIA was one of transition, where he's helped his agency become integrated into the intelligence community," the president said. "That was a tough job, and he's led ably." (Watch Bush's Oval Office announcement -- 2:38)

Goss thanked Bush for the "very distinct honor and privilege" of serving as director of the CIA, and he described the agency as now being "on a very even keel."

"It's sailing well," Goss said. "I honestly believe that we have improved dramatically your goals for our nation's intelligence capabilities, which are, in fact, the things that I think that are keeping us safe."

Negroponte was in the Oval Office when the resignation was announced, but he did not speak.

A senior staffer on the Senate Intelligence Committee told CNN that lawmakers and congressional staffers were caught off guard by the "bizarrely sudden" resignation.

CNN's Pam Benson, David Ensor, John King, Kathleen Koch, Elaine Quijano and Suzanne Malveaux contributed to this report.

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