WASHINGTON — President Bush and congressional leaders pledged Tuesday to investigate the government's response to Hurricane Katrina, but disagreement erupted between Republicans and Democrats over the speed and scope of the inquiry and the need for changes in the Federal Emergency Management Agency.
The White House, meanwhile, was preparing a request for another round of emergency funds of as much as $40 billion. The expanding cost of the recovery and the tone of the debate virtually guaranteed that Katrina would swamp Washington's political landscape long after its floodwaters recede in New Orleans.
The administration has been forced to set aside other priorities while it tends to a natural disaster of immense proportions and defends itself against accusations that a flawed response made matters even worse.
On Capitol Hill, the Republican leader of a Senate committee said she was launching an investigation into the federal response.
Democratic leaders said the administration was not moving quickly enough to determine what went wrong last week and to undertake reforms to make sure any mistakes were not repeated.
Several called for an inquiry by an independent commission; one demanded the resignation of FEMA director Michael D. Brown.
The White House acknowledged that the initial government response to the unfolding tragedy was inadequate, and Bush promised to personally conduct an investigation into the actions of federal, state and local authorities last week.
"What I intend to do is ... to lead an investigation to find out what went right and what went wrong," Bush told reporters at the end of a morning Cabinet meeting.
But the president gave no specifics as to how that investigation would be conducted.
And he said a more immediate priority was responding to the needs of the tens of thousands of residents of New Orleans and other parts of Louisiana and Mississippi who were displaced by the hurricane and the damage it wrought.
Bush said he was sending Vice President Dick Cheney to the region Thursday to assess the effectiveness of post-hurricane recovery efforts.
He said Cheney would work with Homeland Security Secretary Michael Chertoff to remove any "bureaucratic obstacles" that might be slowing progress. The White House worked into the evening on a request for about $40 billion to fund hurricane relief efforts.
The emergency funding would be on top of a $10.5-billion package approved hastily Friday by Congress.
Last week's appropriation "was only a down payment," said Scott Milburn, a spokesman for the Office of Management and Budget. "We're writing the second installment now."
White House officials said the request would be sent to Congress as early as today.
House Majority Leader Tom DeLay (R-Texas) said Congress could complete work on the aid bill by the end of the week.
Senate Minority Leader Harry Reid (D-Nev.) predicted a much greater infusion of cash would be needed for emergency efforts in the affected areas.
He said the recovery effort was costing more than the Iraq war on a daily basis, and that "an initial investment of $150 billion will be needed."
Republican leaders said they wanted to investigate what went wrong with the initial relief effort. But there was no agreement on the nature of the investigation, how quickly it should begin or who should conduct it.
Some Democrats called for an independent group modeled after the Sept. 11 commission appointed by Bush in the wake of the 2001 terrorist attacks on the World Trade Center and the Pentagon.
But DeLay said he did not believe such a commission was necessary. Instead, he called for a joint investigation by both chambers into what he said were the failures of federal, state and local authorities.
Sen. Trent Lott (R-Miss.), who lost his family home to the hurricane, pleaded with colleagues to focus on the daunting task of cleanup and reconstruction before trying to place blame.
"Please don't have a hearing tying up people who need to make decisions," Lott said.
What was needed in the ravaged Gulf Coast area, he said, was manpower. "Anybody in America who can get a chain saw and come to work -- we need that."
Lott issued his plea after Sen. Susan Collins (R-Maine), chairwoman of the Senate Homeland Security and Governmental Affairs Committee, said the government had failed in its fundamental responsibility to protect citizens.
"In its initial response to the catastrophe of Hurricane Katrina, particularly in Louisiana, governments at all levels failed in this obligation," Collins said in announcing that her committee would investigate what went wrong.
There were disagreements that cut across parties over whether Congress had made a mistake when it folded FEMA into the much larger Department of Homeland Security.
Some said FEMA's response to the hurricane was evidence the agency had been harmed by becoming part of a bigger bureaucracy that is focused largely on preventing and responding to terrorist attacks, not natural disasters.