Aid workers struggled to help thousands huddled in makeshift camps in the province in northern Sumatra and to reach remote areas after roads and airstrips were washed away.

Across southern Asia logjams began to ease at airports bursting with hundreds of tons of emergency supplies but relief workers faced a logistical nightmare in distributing them.

"It's absolute chaos," said Titon Mitra of CARE International, which is running 14 survivor camps in Aceh.

The same bleak picture faced aid workers in Sri Lanka, the second worst-hit nation, said Margareta Wahlstrom, United Nations special envoy for tsunami relief.

The UN said 1.8 million survivors needed food in tsunami-hit areas but the world's response in money and resources gave grounds for hope as dehydration, disease and hunger threatened to add to the already huge death toll.

World Bank president James Wolfensohn said his agency could double or triple the $250 million it has promised for regional reconstruction, and would also be looking at debt relief for the poor nations worst affected by the disaster.

"The international system is working," UN Emergency Relief Coordinator Jan Egeland said in New York.

Hundreds of fresh foreign troops poured into Aceh in a race to stop the outbreak of killer diseases among survivors of the tsunami, triggered by a huge earthquake off Sumatra on Dec. 26.

UNICEF said it had reports of children dying of pneumonia in Aceh. Many in refugee camps were sick from a variety of ailments, as well as terrible wounds sustained when the tsunami hit.

A Health Ministry official said he had no reports of a cholera outbreak, but the risk was very high.