UNITED NATIONS: The director of UN humanitarian operations urged Nepal on Wednesday to fast-track clearance and waive taxes on aid shipments which are delaying desperately needed assistance getting to 500,000 people who urgently need food and 100,000 households that still require shelter following two devastating earthquakes.

John Ging told a news conference following his recent three-day visit to Nepal that the UN appeal for $442 million for humanitarian assistance until the end of September is only 46 per cent funded "and we cannot afford to have 30 per cent of the funding going into taxation."

The largest amount for the appeal has come from the Nepali diaspora, and other major contributions have come from the United States, Norway, China, Britain, and Thailand, he said.

Ging said the aid is essential to provide life-saving support to people and should not be sitting in the capital, Kathmandu, where he saw corrugated iron sheeting held up by customs sitting in warehouses.

He said backlogs of essential shelter materials continue at Kathmandu airport and the Indian border due to bureaucratic impediments.

Ging said he was "pleased" to have a positive reaction from officials that he raised these issues with during his trip.

While Ging praised the very large humanitarian response to the magnitude 7.8 earthquake on April 28 and the 7.3 magnitude quake on May 12, he stressed that the numbers of people affected are huge and the monsoon rains have already started.

He said medical services continue to be in very high demand given that many medical facilities were either damaged or destroyed, and 3.9 million people still have very limited access to clean drinking water.

Nepal also faces a very big challenge in getting 1.3 million children back to school because so many schools were destroyed in the quakes, Ging said.