Nearly 200,000 people are homeless and at least 313 dead after Typhoon Bopha swept across the south of the country.
Civil defence chief Benito Ramos said the government's priority was to find 379 people still missing and to build temporary shelters for more than 179,000 others who have been given temporary shelter in schools and government buildings.
The Office of Civil Defence said on Thursday that more bodies had been retrieved from the hardest-hit provinces of Compostela Valley and Davao Oriental, as well as six other provinces, raising the death toll to 313.
Typhoon Bopha ploughed across the major southern island of Mindanao on Tuesday, flattening nearly everything across its 700-kilometre wide path with a blend of hurricane-force winds, floods and landslides.
Al Jazeera's Marga Ortigas, reporting from Compostela Valley, said there had been massive destruction to infrastructure and agriculture in the region, with authorities saying about 80 per cent of the crops planted had been destroyed.
She said rescuers were using helicopters in the search for survivors as wet mud was hindering access for rescue teams on the ground.
At least 200 of the victims died in Compostela Valley alone when the storm struck, including 78 villagers and soldiers who perished in a flash flood that swamped two emergency shelters and a military camp.
"Entire families may have been washed away," said Interior Secretary Mar Roxas, who visited New Bataan on Wednesday.
The farming town of 45,000 people was a muddy wasteland of collapsed houses and coconut and banana trees felled by Bopha's winds.
Towns cut off
Bodies of victims were laid on the ground for viewing by people searching for missing relatives. A man sprayed insecticide on the remains to keep away swarms of flies.
President Benigno Aquino has sent navy ships with food and other supplies to 150,000 people on Mindanao's east coast where three towns remain cut off by landslides and wrecked bridges.
Officials said many of the Mindanao victims were poor migrants who have flocked by the thousands to mountainous, landslide-prone sites like the towns of New Bataan and Monkayo to work at unregulated, small-scale gold mines.
Those two towns alone accounted for half of the deaths, the civil defence office said.
Social Welfare Secretary Corazon Soliman said the government had sought help from the Swiss-based International Organisation for Migration to build temporary shelters for Bopha survivors.
The United States offered aid to the country.
"Our embassies in Manila and Koror [Palau] have offered immediate disaster relief assistance, and we are working closely with authorities in both countries to offer additional assistance as needed," state department spokesman Mark Toner said.
Bopha was the sixteenth and most powerful storm this year to ravage the Philippines, which is hit by about 20 cyclones annually.
In December last year, Mindanao was struck by Washi, a tropical storm which killed more than 1,200 people and left hundreds of thousands homeless.