The director of the U.S. Central Intelligence Agency said Wednesday that it will take another five years to improve the agency's ability to counter al-Qaida and other terrorist threats. CIA Director George Tenet made the comment to the independent commission investigating the 2001 terrorist attacks on New York and Washington.

Director Tenet was one of several witnesses who testified before the commission Wednesday as it probed intelligence failures related to the September 11, 2001 attacks. The commission released an interim report critical of U.S. intelligence agencies, including the CIA regarding how they tracked the activities of al-Qaida operatives before the 9/11 attacks.

Phillip Zelikow is the staff director for the 9/11 commission. He said the CIA knew pieces of the al-Qaida puzzle before the attacks, but was never able to put the information together to provide an overall picture of what Osama bin Laden was planning.

"There were no complete, authoritative portraits of his strategy and the extent of his organization's involvement in past terrorist attacks, nor had the [intelligence] community provided an authoritative depiction of his organization's relationships with other governments or the scale of the threat his organization posed to the United States," he said.

CIA Director Tenet said budget cutbacks hurt the agency during the mid-1990s, but he also acknowledged U.S. intelligence agencies simply made too many mistakes in trying to figure out what al-Qaida was up to.

"We never penetrated the 9/11 plot overseas," he said. "While we positioned ourselves very well with extensive human and technical penetrations to facilitate the takedown of the Afghan sanctuary [for al-Qaida], we did not discern the specific nature of the plot."

In addition to finding out what went wrong before the 9/11 attacks, the independent commission will also make recommendations to Congress to help prevent future attacks.

Some changes in intelligence gathering have already been implemented in the wake of the September 11th attacks, including better cooperation with the FBI, which is responsible for monitoring domestic terror suspects. However, CIA Director Tenet cautioned the 9/11 commission that shoring up the nation's ability to both gather and analyze intelligence information would take a lot longer than most people think.

"It will take us another five years to have the kind of clandestine service our country needs," he said. 'There is a creative, innovative strategy to get us there that requires sustained commitment, leadership and funding."

FBI Director Robert Mueller also testified before the 9/11 commission and said that while the agency has made some improvements to its intelligence gathering operation "institutional change takes time."

Mr. Mueller also said that he opposed one possible intelligence reform in the wake of the 9/11attacks, the establishment of a separate domestic intelligence agency that would take over the FBI's traditional role in that area.

"I do believe that creating a separate agency to collect intelligence in the United States would be a grave mistake," he added. "Splitting the law enforcement and intelligence functions would leave both agencies fighting the war on terrorism with one hand tied behind their backs. A distinct advantage we gain by having intelligence and law enforcement together would be lost in more layers [of bureaucracy] and greater stove-piping [withholding] of information."

The focus on intelligence gathering came one day after the commission issued a report highly critical of the FBI's performance prior to the 9/11 attacks. Recommendations for improving both the FBI and the CIA are expected in the commission's final report due by the end of July.