"What we see is that the figures may be approaching 150,000 dead. The vast majority of those are in Indonesia and Aceh, which is the least assessed area because of logistical constraints," Egeland told reporters.

"It may therefore rise further," he said.

"We will never, ever have the absolute, definite figure because there are many nameless fishermen and villages that have just gone, and we have no chance of finding out how many they were," he said.

Indonesia has emerged as the country worst affected by Sunday's huge earthquake off its western Sumatra island and the tidal waves it spawned, accounting for more than two-thirds of the dead.

Indonesian Health Minister Siti Fadilah Supari said Friday her officials had stopped trying to count the dead and would from now on give only general casualty estimates since the death toll was too large to provide an exact tally, the state Antara news agency said.

The ministry said earlier the final casualty number would likely reach up to 100,000. Its last confirmed figure was 79,940.