WASHINGTON — President Bush intends to seek $40 billion to cover the next phase of relief and recovery operations from Hurricane Katrina, a congressional official said today as leading lawmakers and the White House pledged to investigate an initial federal response widely condemned as woefully inadequate.

One week after the storm spread death and destruction across a swath of the Gulf Coast, Senate Minority Leader Harry Reid, D-Nev., said the total tab for the federal government may top $150 billion.

Stung by the criticism, Bush invited congressional leaders to the White House for an afternoon meeting, their first since the hurricane hit the Gulf Coast and left much of New Orleans underwater.

"Bureaucracy is not going to stand in the way of getting the job done for the people," the president told reporters earlier in the day after meeting with his Cabinet to review storm recovery efforts.

At the Capitol, Sen. Susan Collins, R-Maine, said she intended to hold an initial hearing of the Governmental Affairs Committee next week into the aftermath of the storm. "It will focus on the way ahead," she said. An investigation into the faults of the recovery effort will be deferred until "after the situation is stabilized and people are no longer in danger."

Bush and the Republican majority in Congress sought to underscore their commitment to help for the damaged region while the Senate's top Democrat said the overall cost could top $150 billion.