Further avalanches on a popular trekking route in Nepal have forced rescuers to halt their search for four South Korean trekkers and three Nepali guides who are believed to have been swept away by a snowslide.

Some 200 climbers have been rescued from other parts of the trekking trail and flown to safety by helicopters over the weekend, the Department of Tourism said.

It added fresh smaller avalanches had made it dangerous for rescuers to approach the area where the missing trekkers were last seen.

Mt. Machapuchre, or 'Fishtail,' is one of many in the Annapurna Range that can be seen from the Ghorepani-Gandruk-Poon Hill trekking loop. Credit: AP

A second search mission is being planned for the missing South Koreans and local guides but will have to wait for snow and ice to stop falling before the operation resumes.

The missing trekkers - two women in their 30s and 50s and two men in their 50s - were teachers who were staying in Nepal for volunteer work, according to the ministry.

Friday's avalanche hit along the popular Mount Annapurna circuit trekking route following rains and snow earlier in the week.

The South Korean Ministry of Foreign Affairs said the avalanche hit at an altitude of 3,230 metres (10,600 feet).

It said five other South Korean members of the same team were safe and taking shelter in a lodge.

South Korean president Moon Jae-in vowed the upmost efforts to find the missing trekkers in a Facebook message posted on Sunday.