President George W. Bush has ordered the deployment of 7,000 additional US troops to help desperate survivors of Hurricane Katrinaas he acknowledged the initial federal effort had fallen short.
"Many of our citizens are simply not getting the help they need, especially in New Orleans, and that is unacceptable," Mr Bush said in a live address in the White House Rose Garden.
The president planned to return to the stricken region on Monday, a week after Katrinahit, the White House said. Mr Bush, who rarely concedes errors, spoke a day after touring the stricken region amid withering criticism of the federal response to the hurricane.
Although Mr Bush cut short his four-week vacation to return to the White House on Wednesday, critics say he was slow to grasp the enormity of the disaster as corpses piled up in the streets of New Orleans and survivors struggled with anarchy and a lack of adequate food and water.
Mr Bush said that despite the efforts of relief workers who have been working around the clock, the wide area over which the destruction is spread has created tremendous problems for state and local officials and they need reinforcement.
"The main priority is to restore and maintain law and order, and assist in recovery and evacuation efforts," he said. He said around 21,000 National Guard troops were in the region, 13,000 of them in Louisiana. "Hour by hour, the situation on the ground is improving. "Yet the enormity of the task requires more resources and more troops."
The 7,000 troops will be deployed over the next three days. They will come from the 82nd Airborne Division at Fort Bragg, North Carolina, the 1st Cavalry Division at Food Hood, Texas, the 1st Marine Expeditionary Force at Camp Pendleton, California, and the 2nd Marine Expeditionary Force at Camp Lejeune, North Carolina.
US law bars regular military troops from being used in a domestic law-enforcement role.
Mr Bush said the troops will be operating under the direct command of Lieutenant General Russell Honore, who is heading the military relief effort. The 21,000 National Guard troops already in Louisiana and Mississippi are under the command of the state governors. They are permitted to perform law enforcement duties.
Mr Bush has rejected criticism that his administration has devoted too many resources to Iraq and not enough to domestic preparedness. "I just completely disagree," he said.