Elisabeth Byrs, spokeswoman for the UN Office for Coordination of Humanitarian Affairs, said donor countries had already pledged 74.8 million dollars (59 million euros) in cash and kind but did not specify how much would be sought in total.

Funds raised would be sufficient for just 90 days and would be divided between nine key areas, including food, water and reconstruction, with a main focus on health, she said.

"The phase that we have entered is a reconstruction phase and an evaluation of the needs will be translated into the launch of a flash appeal in Bam on Thursday," Byrs told a briefing at the UN's European headquarters in Geneva.

Jan Egeland, UN under secretary general for humanitarian affairs, is due to launch the appeal during a trip to Iran beginning Tuesday, where he will also deliver a letter from UN Secretary General Kofi Annan to Iranian President Mohammad Khatami.

The massive earthquake that hit Bam on December 26, killing up to 35,000 people, destroyed or damaged two of the city's three hospitals, all of its 23 health centres and 95 out of 96 smaller medical outlets, according to Byrs.

The UN will ask countries and non-governmental organisations to adopt a medical centre to rebuild, she explained.

A number of countries such as France and Japan have already helped to set up 13 field hospitals in Bam to look after the thousands of survivors of the devastating tremor.

The International Federation of the Red Cross and Red Crescent Societies said its emergency services in the city have already treated 1,000 patients.

The World Health Organisation noted that so far there had been no large outbreak of disease as a result of the quake, but agreed that rebuilding health services was a top priority.

A team dispatched to the area by the United Nations Children's Fund reported that 1,800 children lost both mother and father and another 5,000 children had lost one parent, according to UNICEF spokesman Damien Personnaz.

About 12,000 youngsters of school age died in the earthquake, he added.

Personnaz denied media reports that some schools in the city had re-opened. "This is not the case," he said.

The Iranian government and the United Nations have been drawing up a reconstruction plan and appeal for more funds. Authorities have promised to rebuild the city in 18 months.

Donor countries are due to meet in Geneva on Friday to discuss the relief response in Bam.

TERRA.WIRE