Updated

President Bush is cutting short his vacation to head back to the White House Wednesday to meet with members of his Cabinet who are assessing the damage and directing federal aid for victims of Hurricane Katrina (search).

The president will be better able to oversee relief efforts from Washington, where the White House disaster relief task force is meeting Wednesday afternoon, aides say. Bush plans to visit the region himself later this week, a decision urged by lawmakers from the damaged areas.

"Mr. President, the people of Mississippi are flat on their backs. They're going to need your help," Sen. Trent Lott, R-Miss., told Bush in a phone call Tuesday. "I urge you to come to Mississippi. Your visit would be very good for the morale of Mississippians who are hurting right now."

Energy Secretary Sam Bodman told FOX News on Wednesday that the president is likely to release emergency oil supplies from the Strategic Petroleum Reserve. Bodman said he expected the details to be worked out at Wednesday's meeting and an announcement to be made afterward.

On Tuesday, the president urged residents of Louisiana, Mississippi and Alabama not to return yet to their homes. The notice came hours before Louisiana Gov. Kathleen Blanco ordered an evacuation of New Orleans, which is flooding as a result of broken levees.

"We know that many are anxious to return to their homes. It's not possible at this moment," Bush said while appearing at a San Diego naval base to commemorate the 60th anniversary of victory over Japan in World War II. "Right now our priority is on saving lives and we are still in the midst of search and rescue operations."

The response to Hurricane Katrina is being called the largest emergency effort ever in American history.

"The federal, state and local governments are working side by side to do all we can to help people get back on their feet, and we have got a lot of work to do," Bush said.

Because Bush declared the states disaster areas before the storm hit on Monday, many relief teams and resources were pre-positioned for rapid deployment throughout the region. But so many roads are washed out, moving resources is proving impossible in many areas.

"The magnitude of our situation is untenable. It's just heart-breaking," Blanco said Tuesday afternoon.

Also called the worst disaster in the history of the Federal Emergency Management Agency and the worst ever in Louisiana, state and local officials are doing nothing to downplay the devastation.

"What I saw today is equivalent to the tsunami in Indonesia. There are places that are no longer there," said Louisiana Democratic Sen. Mary Landrieu.

FEMA has 23 disaster teams in the region. Hundreds of additional search and rescue teams have been deployed from other agencies around the nation. FEMA has ordered in medical specialists from Washington state, Massachusetts, New Mexico, Ohio, North Carolina, Oklahoma, and Florida.

FEMA's emergency medical teams are designed to be self-sufficient, being able to triage and treat as many as 250 patients over 72 hours. The teams bring their own supplies, including food and medicine.

The teams can handle trauma, pediatrics, surgery, and mental health problems. Two Veterinary Medical Assistance Teams are also included to handle pets and rescue dogs.

The Coast Guard has dozens of air and watercraft conducting search and rescue missions along the Gulf Coast. As of early Wednesday, the Coast Guard had rescued more than 750 stranded people, Capt. Bruce Jones told FOX News. Officials have asked the public in the hurricane-damaged area to report any oil spills or releases of hazardous materials. The Coast Guard response center phone number is 1-800-424-8802.

The Department of Health and Human Services has also dispatched nearly 250 emergency medical personnel to the region. The agency has sent in basic first aid material such as bandages, pads and ice packs as well as blankets and patient clothing, suture kits, sterile gloves, stethoscopes, blood pressure measuring kits and portable oxygen tanks.

More than 390 Transportation Department trucks are trying to deliver more than 1 million ready-to-eat meals, or MREs, millions of pounds of ice and millions of gallons of drinking water.

Nearly 8,000 National Guardsmen have been deployed to aid civilian law enforcement and the restoration of power, shelter and medical assistance. An additional 550 Coast Guard Reservists have been deployed by Department of Homeland Security Secretary Michael Chertoff.

The U.S. Conference of Mayors said Tuesday that the nation's mayors are committed to helping in the recovery from this natural disaster.

"I urge the nation's mayors to contact their constituents, corporate and charitable organizations, and local media to help raise funds for this massive effort now," said Long Beach Mayor Beverly O'Neill, the conference president.

"As we have seen in recent disasters both in the United States and around the world, there are no more charitable and caring people than those in our cities and our nation. As mayors, it is our job to help lead in this effort by doing all we can to direct their energy to what is needed most — and right now that means cash."

Cash donations are also being requested from the American Red Cross, which reported Tuesday that it had served about 40,000 people in 200 shelters across the area. Officials from the Red Cross said it had 185 emergency response vehicles on the scene or en route. These trucks provide breakfast, lunch and dinner to storm victims.

Some 2,000 Red Cross volunteers from across the country were joining workers in the area. The Red Cross asked Americans to provide cash donations to turn around quickly into the resources the aid agency needs. The number for donations is 1-800-HELP-NOW.

Even as federal agencies deploy to the region to help out, several federal facilities themselves have been damaged or disabled by Katrina. Keesler Air Force Base in Mississippi suffered extensive damage to base housing, training facilities and industrial areas. Flooding and downed trees also battered buildings at Homestead Air Force Base in Florida. Power is out at the Army's Camp Shelby in Mississippi.

Pensacola Naval Air Station in Florida and Naval Station Pascagoula in Mississippi were being surveyed for damage.

Besides damage at ports and waterways, NASA reported Stennis Space Center in Mississippi and Michoud Assembly Facility in New Orleans were closed during recovery efforts. NASA's Marshall Space Flight Center, Huntsville, Ala., sustained minor damage and is providing support to Stennis and Michoud.

More than 200 U.S. Postal Service facilities in Mississippi and New Orleans were closed and USPS was trying to get operations up and running at alternate locations so first-of-the-month checks could be delivered to recipients already receiving state and federal aid.

Katrina wreaked havoc on the Gulf region's oil and natural gas industry, a perfect storm to drive up gas and oil prices, which are already being strained by international demand and a limit on the capacity of refineries to produce.

Coast Guard Lt. Cmdr. Jeff Carter said he has heard reports that seven mobile offshore oil-drilling rigs were adrift, and was working with companies on recovery and salvage plans.

Thirty percent of domestic oil production and 20 percent of the nation's natural gas come from the Gulf of Mexico and the region. Officials say no major oil spills occurred and no workers were lost, but it could be days before the companies can fully assess the damage and how long it will take to repair.

Several oil companies have now officially requested loans from the Strategic Petroleum Reserve, but until roads are passable and electricity is restored so that the oil refineries can go back on line, authorizing the release may not provide much relief. Still, Bush has ordered the government to mobilize every available resource and many say a decision on opening the SPR could come anytime in the next 24 to 48 hours.

Click in the video box near the top of the story to watch a report by FOX News' Carl Cameron.

The Associated Press contributed to this report.