House and Senate leaders rushed forward yesterday with promises to quickly restructure the nation's intelligence agencies in the wake of damaging findings by the Sept. 11 commission, casting aside earlier doubts that Congress would tackle such complicated and politically divisive legislation this year.

The White House also signaled that President Bush may consider intelligence reforms before the November elections, contrary to earlier suggestions that such a move was unlikely.

The rapid responses underscored the deep impact of Thursday's 567-page commission report, which chronicled a breathtaking array of failures throughout the government to cope with the al Qaeda threat and protect Americans from terrorist attacks. The bipartisan report, which topped online bookseller lists yesterday, proposes a dramatic restructuring of the U.S. intelligence community and more effective control by Congress, and calls for tougher border controls and other steps to better guard against terrorism.

Commission leaders warned yesterday that the United States is at greater risk of a calamitous attack unless lawmakers and Bush act quickly to adopt the panel's recommendations. Chairman Thomas H. Kean (R) told reporters in Washington that "history will judge severely" a failure to move rapidly, and he criticized earlier statements from some GOP leaders who urged caution in adopting changes.

"To sit in the face of another possible attack on the American people, when your primary responsibility is to protect the American people, is not acceptable," Kean said. "We believe unless we implement these recommendations, we're more vulnerable to another terrorist attack. . . . Time is not on our side."

Senate leaders yesterday announced an agreement reached Thursday night between Majority Leader Bill Frist (R-Tenn.) and Minority Leader Thomas A. Daschle (D-S.D.) that directs key lawmakers to come up with proposals by Oct. 1 for restructuring U.S. intelligence agencies and reorganizing congressional oversight of the issue.

And despite earlier signals of caution from House Speaker J. Dennis Hastert (R-Ill.), he and House Majority Leader Tom DeLay (R-Tex.) said late yesterday that they had directed appropriate House committees to "examine the commission's recommendations, begin hearings in August and report back to us with recommendation for specific legislation in September including specific proposals we will consider before Congress adjourns." They said they expect the committees to announce their schedule for hearings next week.

"The commission has done good work and made some important recommendations about how to improve America's security," the two Republican leaders said.

White House officials said Bush may embrace recommendations for intelligence reform before the November presidential election, but said they were not speeding up a separate review of the nation's intelligence system by another commission appointed by the president as a result of the faulty prewar intelligence on Iraq.

Bush took the 9/11 commission's report with him yesterday to his ranch in Crawford, Tex., officials said, where he plans to work on proposals with aides before returning to Washington on Thursday, the day the Democratic National Convention draws to a close.

Stephen J. Hadley, the deputy national security adviser, is staying with Bush, and national security adviser Condoleezza Rice plans to join him on Monday to work on the recommendations, officials said. Bush also directed White House Chief of Staff Andrew H. Card Jr. to lead a task force to review the recommendations.

The moves would seem to ensure that the Sept. 11 attacks, along with the intelligence failures that preceded them, will remain prominent issues during the last months of the presidential race. The subject poses a political dilemma for the Bush campaign, which has sought to emphasize the president's war on terrorism while dismissing Democratic allegations that he ignored al Qaeda before Sept. 11, 2001, and has increased the terrorism risk by invading Iraq.

As recently as Thursday, Rice urged caution in moving forward with reforms too fast. Acting CIA Director John E. McLaughlin and Homeland Security Secretary Tom Ridge criticized one of the panel's main recommendations for reform: the creation of a national intelligence director in the Cabinet to oversee the government's 15 intelligence agencies. The commission also urges the creation of a National Counterterrorism Center, to coordinate intelligence gathering and operations both domestically and abroad.

Sen. John F. Kerry (D-Mass.), the presumptive Democratic presidential nominee, on Thursday urged rapid action on the Sept. 11 commission's recommendations. Kerry said that if reforms are not enacted and he is elected president, he would immediately convene a security summit to push for changes.

The pointed comments yesterday from Kean and his vice chairman, former Indiana congressman Lee H. Hamilton (D), are the opening salvo in an aggressive campaign by the 10-member commission to lobby for its recommendations. Commission members, who are already appearing on television programs virtually around the clock, plan to fan out across the country in speaking engagements.

Kean said the group is working to enlist relatives of Sept. 11 victims to monitor and lobby federal lawmakers on a district-by-district basis. The panel, whose budget and existence expires by law next month, is also exploring ways to keep itself going independently to keep tabs on the government's progress, Kean said.

The effort is aimed at increasing the pressure on lawmakers and the administration to respond more directly to the commission's calls for reform, according to panel officials. "The status quo always has an army," Kean said. "To besiege that castle is very, very difficult, but that's what we've decided to do."

Kristen Breitweiser, whose husband Ronald Breitweiser died in the World Trade Center, said she and other Sept. 11 relatives "will do whatever we need to do" to push the commission's recommendations. She criticized lawmakers for preparing to recess at the same time U.S. intelligence officials are warning of an increased terrorist threat.

"Our elected officials, the president and Congress need to prove to the American people that they're making national security a number one priority," Breitweiser said.

The decisions by House and Senate GOP leaders to hold hearings next month came after Sens. Joseph I. Lieberman (D-Conn.) and John McCain (R-Ariz.) endorsed legislation to enact the commission's major recommendations. Democratic congressional leaders had signaled that they were prepared to seize on the issue if GOP leaders did not act.

Lieberman and Sen. Susan Collins (R-Maine), the chairman of the Governmental Affairs Committee, said hearings will begin the first week of August.

Congress will return from its recess on Sept. 7 and is scheduled to wrap up work by early October. Collins and Lieberman said the legislation could be dealt with in early October or, failing that, in a post-election "lame duck" session.

Staff writers Mike Allen and Dana Milbank contributed to this report.

Joined by Vice Chairman Lee H. Hamilton, left, Chairman Thomas H. Kean urged swift action on recommendations.