Rescue workers in Vietnam are searching for some 50 people still missing after Tropical Storm Durian lashed the south coast, killing nearly 50 others.
Many thousands of homes were destroyed and hospitals are treating hundreds of injured after Tuesday's severe storm.
Durian earlier hit the Philippines as a typhoon, causing devastating mudslides that buried a number of villages in the Bicol peninsula, south-east of Manila.
The death toll has risen slightly to 543, with 740 people still missing.
Rescuers are working around the clock to open up supply lines to the worst affected areas around the Mayon volcano in the Luzon region.
Machines have been brought in to shift tonnes of sand and volcanic rock to allow relief shipments to get through.
At least 250,000 homes are reported to have been destroyed or damaged, and power and water supplies remain cut off.
But despite a massive effort launched by President Gloria Arroyo to restore basic services by Christmas, officials are warning the reconstruction could take years.
A clean-up is also underway, with officials saying more than 120,000 homes have been damaged or destroyed and some 700 fishing boats swept away.
At least 47 people have died in the south-central provinces of Binh Thuan, Ba Ria Vung Tau, Ben Tre and Vinh Long, officials said.
A further 49 are still missing, and more than 400 have been injured.
"The death toll could rise," said Pham Nhat Quang, a provincial military command spokesman. "Many of the victims are in very bad condition."
There were no reports of flooding, despite warnings of a risk to the low-lying Mekong Delta area.
Vietnamese authorities evacuated thousands of people from vulnerable areas before Durian hit.
The BBC's Bill Hayton, in Hanoi, says the government's decision to authorise local authorities to take all the means necessary to move people from the path of the storm may have saved lives.
Though thousands left voluntarily, he reports, many were forcibly removed from their homes.
He says it is highly unusual for southern Vietnam to experience such a storm in the month of December.
Durian - named after a spiky, Asian fruit - was downgraded to a tropical depression as it headed west across the Gulf of Thailand.