The government also said it was cancelling all visas on arrival for tourists and that those arriving after Saturday would be subject to 14 days of self- quarantine.

Visitors will also no longer be able enter through land borders and must travel through the only international airport, which is situated in the capital, Kathmandu.

Nepal has eight of the highest peaks in the world and the adventurers who head to the country to climb them are a significant source of revenue for the government and the thousands of workers who support the expeditions. So are trekkers and other tourists who flock to the Himalayan nation.

Even before the closure, expedition operators in Nepal had said cancellations for the spring climbing season had been pouring in.

There had been concerns about the new virus and how it could spread among climbers living for weeks on the mountains in shared tents in extreme temperatures. Fever, coughs and colds are already common among climbers.

Nepal so far has had one confirmed case of the virus. The Nepali student who returned home for a holiday from China has already recovered.

AP