National Security Adviser Condoleezza Rice said Thursday that the Aug. 6 briefing to President Bush was the most generalized type of "analytic report" and not a "warning" of imminent attack.

"There was no time, there was no place, there was no method of attack," she said in describing the details of a summer briefing at the president's ranch that is under scrutiny after charges flew Thursday that the president knew details of a Sept. 11-style attack but sat on the information.

Rice said the details were so vague about possible hijackings that the administration didn't want to shut down the national aviation system with an alert.

"Steps were taken. And I'm sure security steps were taken. But you have to realize that when you're dealing with something this general, there's a limit to the amount that you can do," she said.

In a speech Thursday night, Vice President Dick Cheney said congressional Democrats need to be "very cautious" about their criticism of the Bush administration's decision not to disclose the intelligence before Sept. 11.

In his speech at the New York state Conservative Party's annual dinner, Cheney warned Democrats "to not seek political advantage by making incendiary suggestions ... that the White House had advance information that would have prevented the tragic attacks of 9/11."

"Such commentary is thoroughly irresponsible and totally unworthy of national leaders in a time of war," he said.

And first lady Laura Bush, on a 10-day European tour, said Friday that victims of Sept. 11 are being "preyed upon" by those who question whether the president was negligent to terrorist intelligence last summer.

Several Democratic and Republican sources familiar with the intelligence information have described the material as "innocuous." Republican sources earlier in the day suggested the White House describe the information publicly in order to defuse the current controversy.

Democratic sources also said it would be totally inaccurate to characterize the information as a "warning," and said it was consistent with the intelligence assessments that are provided to the Hill on a daily basis.

Senate Minority Leader Trent Lott disputed charges by congressional Democrats Thursday that the House and Senate intelligence panels knew nothing of warnings to Bush last summer about the threat of imminent hijackings of American airliners.

"There's no question that the intelligence committee of the Congress and the administration had reason to suspect that hijackings were a possibility. I don't think anyone knew that they would possibly be used as a missile into a high-rise building," Lott, R-Miss., told Fox News.

Sen. Richard Shelby, R-Ala., ranking member of the Senate intelligence panel, said Thursday that his committee was given a "summary of a summary of a summary" given to the president, but none of the material constituted a "general warning."

Still, Capitol Hill was astir with calls for an investigation into whether the White House knew prior to the Sept. 11 attacks that terrorists linked to Usama bin Laden might be planning to hijack American airliners.

Senate Majority Leader Tom Daschle led the charge, saying, "additional examination of the facts in broader forms" is needed to determine whether the Bush administration failed to adequately protect the public from the Sept. 11 attacks.

"I think once we get beyond the intelligence committee, there are now issues that fall outside of intelligence that somebody is going to have to examine, that somebody I think for the public record is going to have to try to clarify," Daschle said.

Rice said the president was alerted in his daily briefing last August that terrorists might be planning to hijack planes, but the administration was considering the possibility of "traditional hijackings," not suicide missions.

"I don't think anybody could have predicted ... that [terrorists] would try to use a hijacked plane as a missile," Rice said. "There was nothing in what was briefed to the president that would suggest that he would go out and say to the American people, 'Hey, I just read that terrorists might hijack an aircraft.'"

A senior intelligence official said the president was given a list of issues and concerns regarding Al Qaeda, "but the focus of it was that something is up, not that a hijacking is coming."

"If I had been asked on Sept. 10 what are the most significant threats from Al Qaeda, I would not have said hijacking. I would have bet on other kinds of threats," the source said.

White House spokesman Ari Fleischer said some law enforcement agencies were quietly put on alert based on the information given to Bush during a regular intelligence briefing while he was on vacation at his Texas ranch the first week of August.

At that time, the president was informed that a large number of Arabs were seeking pilot, security and airport operations training in at least one U.S. flight school. The appropriate agencies were given the information and urged to identify more possible Middle Eastern students at flight schools around the country.

The White House first confirmed the August briefing Wednesday night in response to the discovery that the FBI's Phoenix office had written a memo in July to FBI headquarters informing the agency that Arabs linked to Al Qaeda were receiving flight instruction.

Rice said she and the president have no recollection of the specific memo, and have asked the FBI to determine whether the memo actually reached their desks.

"I personally became aware of it recently," she said.

Defense Secretary Donald H. Rumsfeld said Friday on NBC's Today that he was unaware of the Phoenix memo "until it showed up in the press very recently."

"The vast majority of the reports and scraps of information that come in tend to be eventually discounted as not being valid, or, at the minimum, not being actionable," Rumsfeld said.

Fleischer said any alert sent out last summer to appropriate agencies to be on the lookout may have prevented the hijackers from using guns to muscle their way to the cockpits. The terrorists reportedly used box cutters and knives to threaten airline crews and passengers.

A senior intelligence official said, "There is less here than meets the eye", adding that the media are "pole-vaulting over mouse (droppings)."

But political powers are already at work. Sen. Joseph Lieberman, D-Conn., said he may attach an amendment to a defense spending bill near completion that would call for an independent investigation of the administration's handling of FBI information.

Sen. Chuck Grassley, R-Iowa, ranking member of the Senate Judiciary subcommittee with jurisdiction over the FBI, has requested that the Justice Department investigate FBI failures to respond to warnings of threats against the United States.

Currently, a combined House-Senate intelligence panel is investigating intelligence failures that led to the intelligence community's failure to prevent hijackers from overtaking four planes on Sept. 11 and flying them into the World Trade Center, the Pentagon and crashing into a field in Pennsylvania.

Daschle said that intelligence committee's inquiry, which began despite White House reluctance, may not be enough to uncover whether the White House sat on assorted clues before Sept. 11 that bin Laden's terror network might hijack American planes

"The White House has said publicly that they were not briefed, that they had no indication about 9/11," he added. "I am ready to listen to any plausible explanation so we can reconcile what we heard from what we are reading."

The information also included details about Zacarias Moussaoui, the alleged 20th hijacker, who was in custody at the time of the attacks. Moussaoui, the lone defendant in the aftermath of the attacks, is charged with conspiring with bin Laden and the 19 suicide hijackers to attack Americans.

Within the case notes of an FBI agent who investigated Moussaoui is the speculation that "he might be planning to fly a plane into the [World Trade Center.]"

Fox News' Carl Cameron and The Associated Press contributed to this report.