The United Nations has sent experts to help with rescue and relief work in Indonesia, India and other Asian countries stricken by powerful earthquakes and tidal waves.

UN spokesman Fred Eckhard said in a statement the secretary-general Kofi Annan was profoundly saddened and extended his sincere condolences to the people and governments of the countries affected.

He added United Nations disaster and coordination teams are being dispatched throughout the region to work with governments of affected countries in providing rescue and relief assistance.

An 8.9-magnitude underwater earthquake struck off the Indonesian island of Sumatra Sunday morning. The quake and its aftershocks triggered tsunamis which hit India, Sri Lanka, Malaysia and four other Asian countries. The death toll from the disasters has surpassed the mark of 10,000.