By Sushil Sharma BBC correspondent in Kathmandu

The Nepalese authorities have announced that Everest climbers from across the world will gather in May to mark the 50th anniversary of the first ascent of the world's highest mountain.

Norgay and Hillary: The original conquerors of Everest

They say they expect nearly half of the 900 people who have climbed Everest and are still living to attend the meeting in the capital, Kathmandu.

One of the first two men, Edmund Hillary of New Zealand, and the first woman to make the ascent, Junko Tabei of Japan, have confirmed their participation.

More than 1,200 people have climbed the world's highest mountain since Hillary and his Sherpa guide, Tenzing Norgay, first scaled the 8,850-metre peak 50 years ago.

Tourism decline

The authorities hope that the international attention the event will receive will help to boost the country's flagging tourism industry.

The number of tourists visiting Nepal fell by more than a quarter last year with just over 200,000 visitors, according to the Nepal Tourism Board.

The fall has been blamed on publicity about the security situation due to the Maoist insurgency and a slump in world tourism following the terrorist attacks in the United States, in September 2001.

Tourism is a major source of Nepal's foreign currency earnings and employment.

Its revival is crucial for the country's battered economy which last year shrank for the first time in more than 20 years.