"What I intend to do is lead an investigation to find out what went right and what went wrong," Bush said.
"We still live in an unsettled world. We want to make sure we can respond properly if there is a WMD (weapons of mass destruction) attack or another major storm."
Bush said now is not the time to point fingers and he did not respond to calls for a commission to investigate the response.
"One of the things people want us to do here is play the blame game," he said. "We got to solve problems. There will be ample time to figure out what went right and what went wrong."
A congressional official, meanwhile, said Bush would seek $40 billion to finance the next phase of relief and recovery operations.
One week after the storm spread death and destruction across a swath of the Gulf of Mexico coastline, Senate Democratic leader Harry Reid said the total federal cost may top $150 billion.
Stung by the criticism, Bush met congressional leaders in the White House on Tuesday, their first meeting since the hurricane hit the Gulf Coast and left much of New Orleans under water.
"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 he met his cabinet to review storm recovery efforts.
At the Capitol, Republican Senator Susan Collins 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 stabilised and people are no longer in danger".
"What I intend to do is lead an investigation to find out what went right and what went wrong"
US President George Bush
Congress approved $10.5 billion as a down payment for hurricane relief last week.
One official, speaking on condition of anonymity, said it was possible Democrats would request as much as $50 billion as a next instalment.
Senate Democratic leader Reid said: "I believe that the recovery and relief operations will cost up to and could exceed $150 billion."
An aide to Reid, Rebecca Krishna, said: "Our priorities right now are targeted assistance for healthcare, housing and education."
Apart from the investigation announced by Collins and
Democratic Senator Joseph Lieberman, the Senate Energy Committee arranged hearings on petrol prices.
The hurricane disrupted oil production and distribution in the Gulf of Mexico, and petrol prices that had already been rising spiked sharply last week in some areas of the country.
Former presidents Clinton and
Bush are raising funds for relief
Former president Bill Clinton and his wife, Democratic Senator Hillary Rodham Clinton, have called for the appointment of an independent commission to investigate what went wrong.
They said the commission should be similar to the bipartisan commission that investigated the 11 September 2001 attacks.
Bush told reporters he was sending Vice-President Dick Cheney to the Gulf Coast region on Thursday to help determine whether the government was doing all that it could.
White House spokesman Scott McAllen said Bush also was
increasing what he described as a sizable personal contribution to the Red Cross and also was sending money to the Salvation Army.
Meanwhile, Bush objected to references to displaced Americans as "refugees".
"The people we are talking about are not refugees," he said. "They are Americans and they need the help and love and compassion of our fellow citizens."
The president raised the subject during a meeting with service organisations that are helping with the relief effort.
"I believe that the recovery and relief operations will cost up to and could exceed $150 billion"
Senate Democratic leader
In another development, the commander of the Army's 82nd
Airborne Division said that its paratroopers plan to use small boats, including inflatable craft, to launch a new search-and-rescue effort in flooded areas of central New Orleans.
There has been heavy criticism of the government's response to the hurricane.
Bush did not respond directly when asked if anyone on his disaster response team should be replaced.
Earlier, McAllen rejected suggestions that the poor, and particularly blacks, had been abandoned when New Orleans
"I think most Americans dismiss that and know that there's just no basis for making such suggestions," he said.