Kathmandu: Nepal has cleared more than 300 mountaineers to climb Mount Everest after they had to abandon last year's efforts when an ice avalanche killed 16 guides in the mountain's deadliest disaster, an official said Friday.

The government will extend last year's permits without charging new fees, according to the head of Nepal's tourism department, Tulasi Gautam.

The extended permits can be used at any time through 2019, eliminating worries that the climbers would be unable to agree with their original trekking groups on a single time period to return.

The climbers can join any group, he said, or they can opt to pay extra to attempt the summit individually as the fees for group climbing and solo climbing are different.

The three-month climbing season for Everest, the world's tallest mountain, begins in March. Nepal also pledged recently to improve weather forecasting, security and rescue efforts, and has cut climbing fees this year to $11,000 per climber from $25,000.

Last year, a sudden fall of ice struck a group of Sherpa guides hauling gear near base camp, killing 16 Sherpas in the worst single disaster on Everest.