The UN Secretary General Kofi Annan has warned that areas hit by the Asian tsunami a week ago could take up to ten years to recover.
Almost 130,000 people died in last Sunday's South East Asian tsunami disaster, according to the latest figures.
However, relief agencies predict the number will rise to 150,000 in the coming days.
The UN says 1.8 million survivors of the disaster need food but that it could be two more weeks before some isolated communities are reached.
Aid supplies have begun to reach the remote areas of Aech province in Indonesia, the area worst affected by the disaster.
Food is being air-dropped in remote parts of the province, but a shortage of manpower and fuel supplies have hampered distribution.
EU Development Aid Commissioner Louis Michel is in Sri Lanka to see the devastation firsthand, while US Secretary of State Colin Powell is also due in region to assess the damage and help co-ordinate relief efforts.
Concern over fate of children
Aid agencies have expressed serious concern about the fate of children who survived the destruction last weekend.
UNICEF said it believed half of those thought to have died in the disaster were children.
Meanwhile, the British Prime Minister, Tony Blair, has said the Asian disaster will require a long-term commitment from the international community.
Mr Blair said that what happened in Asia last Sunday affected the whole world.
Donation contact numbers
The following are contact numbers for some of the aid agencies appealing for donations for the humanitarian operation in the wake of Sunday's disaster in southern Asia.
Irish Red Cross: 1850 50 70 70
Concern: 1850 410 510 / from NI 0800 410 510
Trócaire: 1850 408 408 / from NI 0800 912 1200
UNICEF Ireland: 1850 767 999 / from NI 08457 312 312
GOAL: 01 2809779
Oxfam Ireland: Lo-call 1890 60 60 65 / from NI 0845 303 0337
The Hope Foundation: 021 4292990
Disasters Emergency Committee (UK umbrella body): 0870 60 60 900
