The United Nations and international donors on Thursday faced an unusual problem as they sought to rally help for victims of the Indian ocean tsunami: not a shortage of money, but a surfeit - or at least far more promised cash than they can use in the coming months.

An outpouring of public donations and government pledges from around the world has created an embarrassment of riches. The $5bn promised amounts to about $1,000 for each of the estimated 5m people affected, much more than the typical annual income of a Sri Lankan fisherman or an Indian villager, let alone an African peasant.