The dispute between Thailand and Cambodia goes back to 1962 when the International Court of Justice ruled that the temple belonged to Cambodia, but failed to make a decision on the land adjacent the complex, giving rise to constant spats between the two nations.  Although perched on a hill top in Cambodian territory, the temple is easily accessible only from the Thai side.

After years of negotiations, the dispute flared up again in 2008, when UNESCO decided to add the temple to its list of world Heritage sites, which would have required Thailand to make it accessible from its side of the border.

Since then, Thai and Cambodian troops have clashed. In the latest incident in April 2009, four Thai soldiers died.

Major General Chamlong Srimuang, leader of the People’s Alliance for Democracy (PAD) who led the recent protest in front of UNESCO’s Bangkok headquarters, said that the border was drawn by French colonial experts, but that Thailand never accepted it. He also slammed the Thai government for not putting sufficient pressures on UNESCO to solve the issue. In his view, the government should boycott the session.

“Even though Thai representatives will attend the conference,” he said, “there is nothing on their agenda to indicate that Thailand plans to protest in the matter. If UNESCO has accepted the Temple of Phra Viharn (alternative spelling) case, it will be to the disadvantage of Thailand,” he added.

Yesterday, Thai Prime Minister Abhisit Vejjajiva said that the Thai delegation at the World Heritage Committee session would defend Thailand’s rights and interests.

"We think the World Heritage Committee should not consider this [Cambodia’s] plan until Thailand and Cambodia have agreed upon the demarcation line," Abhisit said.

"The United Nations and its related agencies were established to promote peace. The UNESCO World Heritage Committee needs to review why its world-heritage inscription often turns tourist zones into areas of conflict," he added.