The 17 Chinese monks and officials invited to this week's World Fellowship of Buddhists (WFB) conference in South Korea abruptly flew home Wednesday after lodging a complaint about the presence of a Tibetan delegation.

The Jogye Order of Korean Buddhism called their departure "extremely regrettable" and accused them of "lacking the least respect and consideration" for what was supposed to be a purely religious event.

"The Chinese delegates only prioritised their own political agenda by refusing to accept the presence of a Tibetan delegation officially registered as a member of the WFB," it said in an unusually strongly worded statement.

"The WFB conference should be a purely religious exchange that rules out political interests... we demand that the Chinese delegation offer a sincere apology and promise it will never happen again," it said.

The Jogye Order also said it actively sympathised with the free religious activities of Tibetan Buddhists and would "seriously reconsider" ties with Chinese Buddhists.

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

The event 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 refused in the past to grant a visa for Tibet's exiled spiritual leader the Dalai Lama, apparently for fear of offending 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.