BEIJING (AFP) - China cancelled all spring climbs on the north face of Mount Everest, state media said Monday, after an earthquake in neighbouring Nepal triggered a deadly avalanche elsewhere on the world's highest mountain.

More than 400 climbers have descended to safety in Tibet since Saturday's quake, Xinhua News Agency reported, citing the regional sports bureau.

Climbers stranded for two days at high altitudes on the Nepalese side of the mountain were rescued by helicopters Monday.

Rescue teams in three helicopters were running missions to Camps One and Two following Saturday's avalanche that killed 18 people further down the mountain at base camp.

The 150-odd stranded climbers rescued Monday in Nepal, who were not thought to be seriously injured, had their land route down the mountain blocked by slabs of ice and snow brought down in the avalanche.

There were more than 800 people at different altitudes on the 8,848-metre peak when the avalanche hit.

It was triggered by Saturday's massive earthquake which has killed more than 3,500 people across Nepal and devastated parts of the capital Kathmandu.

China's state media says 20 more people died in Tibet.

Nepal has not yet decided whether to halt expeditions on its side of Everest.

"It is possible that climbing might not continue this year. However, there has been no official decision," said tourism department head Tulsi Gautam.