"Today, we begin the rehabilitation phase of our response to the disaster of the four storms," she said in the town of Infanta on the east coast, which bore the brunt.

Damage to crops, fishing and infrastructure is estimated at 4.69 billion pesos ($83 million). It will take weeks to restore power to the worst-hit areas, clear roads and rebuild bridges.

Teams of army and navy engineers have begun repairing half a dozen bridges after clearing 35 km (20 miles) of highway to Infanta, one of three towns that were badly hit.

Also on Saturday, the US Marines turned over $1 million worth of tents, generators, blankets, medical supplies and water containers to Philippine disaster officials as it pulled out 650 troops after two weeks of relief operations.

Nearly 1,800 people are dead or missing in eastern and northern provinces on Luzon island after a typhoon and three tropical storms in two weeks set off torrents of water, mud, boulders and logs that swept away villages and bridges.

Close to four million Filipinos have been affected. With disease a major worry, the U.S Marines helped speed up efforts to get food, clean water, medicine and shelter to 880,000 people marooned by floods and landslides.

Arroyo thanked Washington for its help in the relief effort, saying the role played by US troops in delivery of emergency rations "speaks of the mighty ties that are shared by time-honoured allies across the Pacific".

She said the $7 million in total US assistance was the biggest contribution by an individual foreign government to her government's relief efforts.

Manila has received close to 100 million pesos ($1.8 million) in cash, emergency rations and equipment from the international community, including foreign non-government organisation.

International aid agencies continued to appeal for support to combat potential disease outbreaks in flood-stricken areas, saying more than $8 million in additional aid was needed during the next three months.

Logging has been blamed for making a natural disaster worse. Arroyo has ordered cancellation of all permits to cut and haul trees but timber companies have scuttled previous attempts in Congress to ban logging.