"They will be conducting humanitarian and relief assistance upon the request of the Philippine government and the Armed Forces of the Philippines," said US Navy Captain Dennis Williams, who is attached to the US embassy here.

A detachment of 40 marines from Okinawa, Japan, arrived at the former US military base in Clark, 80 kilometers (50 miles) north of Manila, said Williams.

At least 560 more from the same base will arrive in the next few days on board a CH 46 medium-lift helicopter and a CH 53 heavy-lift helicopter, Williams added.

Williams told Agence France-Presse in a separate interview that the marines would stay in the Philippines "for as long as the Philippine government wants them to."

Williams said the US Marines would be going to Quezon, one of the areas hardest hit by typhoons "within 48 hours."

"There has been a secured landing zone in Quezon province where it will be safe for the US helicopters to land and the Armed Forces of the Philippines will be the one to take care of the crowd control and security precautions in the area," he said.

Two US C-130 Hercules transport aircraft arrived in Clark on Tuesday night carrying tons of food and clothing for victims of the storms that left a trail of devastation across much of Luzon last week.

Two navy Seahawk helicopters from the USNS Stockham have begun ferrying food and much needed medical supplies into the devastated town of Real one of the worst hit areas on the east coast of Luzon.

It is expected that a further 12 US military helicopters from Okinawa will join them shortly.

A seven-man US "combat lifesaver team" also arrived to help with the storm casualties amid growing health concerns.

The National Disaster Coordinating Council (NDCC) said over a thousand people were killed or missing after four successive storms spawned flashfloods and landslides in Luzon.