An official with the UN Development Program (UNDP), who just returned from assessing the damage caused by last month's deadly earthquake in Nepal, said Tuesday that a race against the clock is on to provide shelter for about 500,000 families before the arrival within weeks of monsoon rains in the mountainous country.

Magdy Martinez-Soliman, UNDP's Assistant Administrator and Director of the UNDP Bureau for Policy and Program Support, said at a press conference that "The UN has made a general international appeal worth 423 million US dollars for its agencies working in Nepal," adding "The slow response to date is worrying because we are working against the clock and many people are still without permanent shelter."

He said rebuilding work in Nepal is "a daunting task" and initial damage results ranged from 1 billion to 10 billion US dollars. He added the real cost, determined through a proved methodology called the Post Disaster Needs Assessment, should be available in the first week of July.

The main principles, he said, are to give priority to temporary housing and shelter before the monsoons rains and involve the communities themselves in safe demolition, reconstruction and re- launch of economic activities and secure livelihoods.

According to him, the Nepalese government has listed housing, government buildings for public service provision, securing large infrastructure that might have been fragilized, and working on historical and cultural heritage sites, which are important to Nepal's economy, as the top four priorities.

Many Nepal's World Heritage Sites designated by the United Nations Educational, Scientific and Cultural Organization have been heavily damaged in the deadly tremor.

However, the UN official noted that despite the intensity of the April 25 tumbler which killed more than 8,000 people, the Himalayan nation was spared the loss of essential communication facilities.

There is still a small but working airport in the capital of Kathmandu for outside aid to arrive, plus intact road, electricity and telephone networks in the country, he said.

Martinez-Soliman said that several UN agencies are using the services of and working with Sherpas to reach isolated villages.

Aid was coming in from around the world, Martinez-Soliman said, with China and India in the lead with New Delhi's troops first in bringing aid an equipment.

"The tents of the Chinese aid were next to the Norwegian Red Cross, next to OCHA (UN Office for the Coordination of Humanitarian Affairs), next to UNDP next to the DFID (the Department for International Aid of the United Kingdom), the USAID, you name it, it's one after the other, a very large number of people and organizations and countries who have decided to provide support," he said.