UN spokesman Fred Eckhard said Mr Annan wanted to appoint a special envoy not only to focus on the cleanup and reconstruction but to try to make progress on resolving conflicts with rebels in the two worst-hit countries – Indonesia and Sri Lanka.

He said the appointment would give Mr Clinton a chance to use his political skills to tackle the longstanding conflicts between rebels in Indonesia’s Aceh province, who have been fighting for independence since 1976, and Tamil Tiger rebels in Sri Lanka who have been fighting for a separate homeland since 1983.

“The secretary-general is confident that (former) president Clinton will bring energy, dynamism and focus to the task of sustaining world interest in the vital recovery and reconstruction phase following the tsunami disaster,” said the announcement. .

“He believes that no one could possible be better qualified for this task,” the statement said.

Mr Clinton said that he looked forward to serving as Mr Annan’s special envoy starting next month and would have more to say about the job at that time.

Soon after the disaster, US President George W Bush named Mr Clinton and his father, ex-President George HW Bush, to head a US wide private fundraising to help countries devastated by the tsunamis.

The two ex-presidents have been travelling throughout the United States raising money and HW Bush said last week they hoped to go to the tsunami-ravaged Indian Ocean region to illustrate the need for continued financial help from Americans to rebuild the area.

Mr Clinton said he would continue to focus on his work with ex-president Bush “to urge people to contribute to this cause, and the two of us hope to visit the region together later this month”.

Mr Annan and Mr Clinton have decided that a formal announcement and joint appearance will take place after the former US president returns from the region later this month.