PORT-AU-PRINCE - The United States was sending more troops on Monday to help protect a huge relief operation in Haiti from marauding looters as tens of thousands of earthquake survivors waited desperately for promised food and medical care.

Gangs of looters still prowled demolished streets of downtown Port-au-Prince filching goods from destroyed shops with little police presence, but some signs of normality returned as street sellers emerged with fruit and vegetables.

We do not have the capacity to fix this situation. Haiti needs help ... the Americans are welcome here. But where are they? We need them here on the street with us, said policeman Dorsainvil Robenson, as he chased looters.

Some 2,200 Marines with heavy earth-moving equipment, medical aid and helicopters were arriving on Monday, said the U.S. Southern Command, which aims to have 10,000 U.S. troops in the area for the rescue operation.

World leaders have promised massive amounts of assistance to rebuild Haiti since Tuesday's quake killed as many as 200,000 people and left its capital, Port-au-Prince, in ruins.

European Union institutions and member states have offered more than 400 million euros (352 million pounds) in emergency and longer-term assistance to Haiti, which even before the disaster was already the poorest state in the Western Hemisphere.

Aid workers struggled to get food and medical assistance to the survivors, many of them injured, hungry and thirsty and living in makeshift camps on streets strewn with debris and decomposing bodies.

The situation is very tough on the ground, including for agencies and countries rushing to help. Minimal survival even for staff there is an issue, the head of the World Health Organisation, Margaret Chan, said in Geneva.

Nearly a week into the crisis, international aid was only just starting to get through to those in need, delayed by logistical logjams and security concerns.

SECURITY CRITICAL, DONORS MEET

Haitian President Rene Preval said on Sunday U.S. troops will help U.N. peacekeepers keep order on Haiti's increasingly lawless streets, where overstretched police and U.N. peacekeepers have been unable to provide full security.

Speaking on ABC's This Week, the commander of the U.S. military operation in Haiti, Lieutenant General Ken Keen said: We are here principally for a humanitarian assistance operation, but security is a critical component. ... We are going to have to address the situation, the security.

In an indication of the sensitivity of U.S. soldiers operating in a Caribbean state where they have intervened in the past, Venezuelan President Hugo Chavez accused Washington of occupying Haiti undercover.

Canada will host a meeting of foreign ministers in Montreal on January 25 to look at Haiti's needs, the Canadian government said.

Senegalese President Abdoulaye Wade, meanwhile, proposed that African nations offer Haitian survivors the chance to resettle in Africa the land of their ancestors.

Africa should offer Haitians the chance to return home. It is their right, Wade said on his website. Local media quoted Senegalese officials as saying the West African country was ready to offer parcels of fertile land to Haitians.

The president of the Inter-American Development Bank, Luis Alberto Moreno, will visit Haiti on Monday and attend a donors meeting in the Dominican Republic to start discussing Haiti's reconstruction needs, a bank spokesman said.

Former U.S. President Bill Clinton, the U.N. Special Envoy to Haiti, was due to meet on Monday with Preval, whose cabinet met outside police headquarters on Sunday in a circle of white plastic chairs due to the collapse of the presidential palace.
Clinton was to bring aid supplies and determine more about what Haiti needs.

POLICE PURSUE LOOTERS

Streets piled with debris slowed the delivery of medical and food supplies, but there were signs of progress as international medical teams took over damaged hospitals where seriously injured people had lain untreated for days.

Rescue teams also raced against time to find people alive under the rubble of collapsed buildings, with more successful rescues of survivors reported on Sunday.

Trucks piled with corpses were ferrying bodies to hurriedly excavated mass graves outside the city, but tens of thousands of victims are still believed buried under the rubble.

With people turning more desperate by the day, looters have swarmed smashed shops in downtown Port-au-Prince, fighting each other with knives, hammers, ice-picks and rocks while police tried to disperse them with gunfire. At least two suspected looters were shot dead on Sunday, witnesses said.

Heavily armed gang members have returned to the Cite Soleil shantytown since breaking out from prison after the quake.

Whether things explode is all down to whether help gets through from the international community, said police commander Ralph Jean-Brice, in charge of Haiti's West Department, whose force is down by half due to the quake.

Local mayors, businessmen and bankers told Preval that restoring law and order was essential for reviving at least some commercial activity.

FOOD FROM THE AIR

The U.S. military said it was doing its best to get as many planes as possible into Port-au-Prince, after aid agencies complained shipments of aid had not been allowed to land at the U.S.-controlled airport.

The airport's control tower was knocked out by the quake and U.S. military air controllers were operating from a radio post on the airfield grass, said Colonel Buck Elton, commander of the U.S. military directing flights at Haiti's airport.

More than 30 countries have rushed rescue teams, doctors, field hospitals, food, medicine and other supplies to Haiti since Tuesday's quake, choking the airspace and the ramp at the small airfield.

Although a few street markets had begun selling vegetables, charcoal, chicken and pork, tens of thousands of earthquake survivors across the city were still clamouring for help.

There were jostling scrums for food and water as U.N. trucks distributed food packets and U.S. military helicopters swooped down to throw out boxes of water bottles and rations.

We haven't moved for four days, only God knows how long we can survive like this, but there are no jobs and no houses, said Marie Gracieuse Baptiste, a single mother with four children, sheltering at one improvised survivors' camps.

A crude sign at the camp's entrance read: People needs water, food.

(Additional reporting by Tom Brown, Joseph Guyler Delva and Carlos Rawlins in Port-au-Prince, Louis Charbonneau at the United Nations, Frank Jack Daniel in Caracas, Mark John and Diadie Ba in Dakar, and David Brunnstrom in Brussels, writing by Anthony Boadle and Pascal Fletcher, editing by Sandra Maler)