The 9/11 Congressional panel will hear some troubling information next week from aides of former President Clinton:

Senior Clinton administration officials called to testify next week before the independent commission investigating the Sept. 11 attacks say they are prepared to detail how they repeatedly warned their Bush administration counterparts in late 2000 that Al Qaeda posed the worst security threat facing the nation — and how the new administration was slow to act.

They said the warnings were delivered in urgent post-election intelligence briefings in December 2000 and January 2001 for Condoleezza Rice, who became Mr. Bush's national security adviser; Stephen Hadley, now Ms. Rice's deputy; and Philip D. Zelikow, a member of the Bush transition team, among others.

Richard Clarke, Clinton's counterterrorism coordinator, whose book, Against All Enemies : Inside the White House's War on Terror--What Really Happened, is being released Monday, says:

...the warning about the Qaeda threat could not have been made more bluntly to the incoming Bush officials in intelligence briefings that he led. At the time of the briefings, there was extensive evidence tying Al Qaeda to the bombing in Yemen two months earlier of an American warship, the Cole, in which 17 sailors were killed. "It was very explicit," Mr. Clarke said of the warning given to the Bush administration officials. "Rice was briefed, and Hadley was briefed, and Zelikow sat in."

The White House does not dispute that it received the information. The dispute is over what was done with the information. The Clinton aides say the Bush administration sat on it and that terrorism was a low priority until Sept. 11. Bush says he made terrorism a top priority and followed through on Clinton's policies.