Chinese delegates taking part in a religious event in South Korea abruptly flew home Wednesday in an apparent protest against Tibetan participation, organisers said.

The 17 Chinese monks and officials invited to the World Fellowship of Buddhists (WFB) conference ending this Friday returned home a day after lodging a complaint about Tibet's presence, said a spokeswoman for the organising committee.

On Tuesday three Tibetan delegates were forced to leave a delegates' assembly meeting after Chinese officials threatened to boycott the meeting, she said.

"The WFB secretary-general accepted the Chinese demand that the Tibetans leave so the meeting could go smoothly," she said, calling the decision by the WFB chief "embarrassing".

The three Tibetans are still taking part in other events at the five-day conference and the Chinese left South Korea Wednesday morning, she said.

About 400 delegates from some 30 countries are taking part in the two-yearly event in the southern city of Yeosu.

It drew attention after Seoul's government, in a rare move, approved a visa for Samdhong Rinpoche, an ex-prime minister of Tibet's government-in-exile.

South Korea has several times in the past refused to grant a visa for Tibet's exiled spiritual leader the Dalai Lama, apparently for fear of offending China.

Rinpoche, the highest Tibetan official to visit South Korea, is a special guest at the meeting in addition to the three official Tibetan delegates.

Organisers initially sought to invite the Dalai Lama himself to the Yeosu conference but later ditched the plan out of consideration for China.

Beijing considers the Dalai Lama a "splittist", despite his calls for autonomy rather than independence for Tibet, and has stepped up pressure on world leaders not to meet him.