U.N. Secretary-General Ban Ki-moon is appealing to the international community for $550 million to meet Haitian earthquake victims' most urgent needs. Some three million people have been affected by the quake and Red Cross officials estimate the death toll at 45,000 to 50,000. Right now, the most important priority is to get water, food and tents to the survivors.

Mr. Ban said he would go to Haiti next week to see the destruction for himself.  "Preliminary estimates from our U.N. emergency teams show widespread damage to infrastructure in Port-au-Prince and other affected areas, with as many as 50 percent of buildings in the worst- hit areas damaged or destroyed," he said.

He said many of the capital area's three million residents are without access to food, water, shelter and electricity nearly 72 hours after the powerful earthquake, and he is appealing to the international community for $550 million to meet those immediate needs.

The window of opportunity to save those beneath the rubble is beginning to close, but Mr. Ban said search and rescue operations are continuing "in an expedited way". He said the U.N. is also coordinating aid distribution, but difficult logistics and limited capacity at the airport are slowing relief efforts. "A major humanitarian effort is now well underway. Although it is inevitably slower and more difficult than any of us would wish, we are mobilizing all resources as fast as we possibly can," he said.

The World Food Program is at the forefront of that effort. The agency began feeding 8,000 people on Thursday. That number is expected to increase to one million within two weeks and two million people within a month.

Dead bodies litter the streets of the Haitian capital and estimates of the death toll have ranged from the tens of thousands to the hundreds of thousands.  Red Cross officials estimate 45,000 to 50,000 dead. Fears of disease are also growing. The U.N. humanitarian chief, John Holmes, said 9,000 bodies were collected on Thursday and those efforts are continuing today.

The U.N. has a huge presence on the island, and when all their missing personnel are accounted for, the organization will likely have suffered its biggest loss of staff ever.

Mr. Ban's spokesman, Martin Nesirky, said so far 37 U.N. personnel are confirmed dead. Another 330 remain unaccounted for.  About 100 of them are believed to be trapped beneath the rubble of the Hotel Christopher, which served as the U.N. mission's headquarters. Many others are believed to be in the collapsed Montana hotel, where many staff lived.