Areas hit by the Asian tsunami could take up to 10 years to recover, the UN secretary general has warned. Kofi Annan spoke of the "sheer complexity" of the relief effort, which is spread across a dozen nations. Mr Annan will travel to Indonesia on 6 January to take part in a meeting of world leaders to discuss further aid.
Aid supplies are piling up in regional warehouses but in some places heavy rain has provided an extra obstacle to delivering them to outlying areas. Survivors are still emerging from the ruins left by the huge quake-triggered waves, which struck a week ago.
At least 124,000 people have been confirmed dead around the rim of the Indian Ocean, with Indonesia's Aceh province worst hit.
The UN has warned the final death toll is likely to be more than 150,000 - and may never be known.
US Secretary of State Colin Powell will travel to Asia on Sunday to see the damage first hand.
He will be accompanied by Florida Governor Jeb Bush, the president's brother, who has dealt with the aftermath of several powerful hurricanes in his state in recent months.
Clusters of survivors
In Indonesia, aid is finally being distributed, but only in small quantities, says the BBC's Jonathan Head. US military helicopters have visited some remote areas but even they have been unable to land, and are having to airdrop aid. The aid operation in Aceh remains without a visible strong leadership. In this sensitive region - scene of a long-running conflict between Jakarta and separatist rebels - the government is unwilling to allow the US military unfettered access, says our correspondent, and there are few UN personnel on the ground.
But speedy, well-led and co-ordinated action is crucial to save the isolated clusters of survivors spotted on the Sumatran coast and islands, who may have spent a week without food and clean water.
In Sri Lanka, heavy rains have brought flash flooding, cutting off parts of the east and south-east of the island and seriously disrupting aid distribution. Fears of an outbreak of waterborne disease among the hundreds of thousands of people thought to be flocking to emergency camps are high.
There are similar fears in Aceh, where heavy rains have also hit. But there have been amazing stories of survival. The Indonesian Red Cross is reported to have dug a man out from under the ruins of a house in the provincial capital Banda Aceh after hearing his cries for help.
And on India's remote Andaman and Nicobar Islands, a woman who escaped the killer waves gave birth in the forest, AP news agency reported. She named her son Tsunami.
In other developments:
• Aid supplies have now been air-dropped onto all of the Andaman and Nicobar islands, says the military commander in charge of the relief operation there, after strong criticism from survivors that aid was slow to arrive
• Strong aftershocks shake the region, causing panic among survivors
• Reports emerge of more than 1,000 children dying in a remote school in the Indian state of Tamil Nadu where they tried to take refuge during the disaster
Donations soar
The UN's relief co-ordinator Jan Egeland said $2bn in aid had been pledged so far from 40 countries - exceeding donations promised for all other humanitarian appeals by the UN in 2004 put together.
Japan became the single largest donor on Saturday with $500m.
"The international compassion has never been like this," Mr Egeland said.
He said the aid effort would focus on feeding one million Indonesians and 700,000 Sri Lankans for months to come.
"The biggest constraints are the logistical bottlenecks," he told reporters at UN headquarters in New York.
"We need to make small, damaged airstrips some of the busiest airports in the world."
CONFIRMED DEATH TOLLS
1. Indonesia: 80,246
2. Sri Lanka: 28,627
3. India (inc Andaman and Nicobar Is): 8,955
4. Thailand: 4,812
5. Somalia: 142
6. Burma: 53
7. Maldives: 73
8. Malaysia: 66
9. Tanzania: 10
10. Seychelles: 1
11. Bangladesh: 2
12. Kenya: 1
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