The move for a peaceful resolution was reaffirmed by senior Thai and Cambodian diplomats at the Association of Southeast Nations (Asean) foreign ministers meeting in Singapore.

George Yeo, Singapore's foreign minister and former Asean secretary-general, said the 10-member group urged the two countries "to exercise utmost restraint and resolve this issue amicably".

"Both sides affirmed that they would ... exert their utmost efforts to find a peaceful solution to the issue," Yeo said on Sunday.

Preah Vihear temple

The 11th-century temple was built during the reign of King Suryvarman I during the 600-year Khmer empire.

Built to honour the Hindu god Shiva, the temple has withstood decades of war.

In 1998, hundreds of Khmer Rouge guerrillas made their final surrender at the temple.

Unesco deemed it a World Heritage site for its location, rare architecture, religious function and carved stone ornaments.

But Thailand and Cambodia have both expressed pessimism about what the talks can achieve.

Brigadier Chea Keo, commander of the Cambodian forces in the area, said on Sunday that he had little faith in the talks because Thailand insists that the land near the 11th-century temple is within its border.

"We have very little hope about the negotiations," Chea Keo said.

Cambodia maintains that Thai troops are trespassing on its territory.

Samak Sundaravej, the Thai prime minister, said in his weekly Sunday television show that the negotiations will not be easy because both sides are sticking to their original positions.

Hun Sen, the Cambodian prime minister, said in a letter to Samak dated Saturday that a previous international court ruling showed that Thailand was wrong.

The letter said the map used in the 1962 ruling by the International Court of Justice shows that the temple "is legally located approximately 700m inside Cambodian territory".

"Nonetheless, I have full confidence that our joint efforts will result in a mutually satisfactory solution to [our] current problem," Hun Sen said.

The conflict over territory surrounding the ancient Hindu temple escalated earlier this month when Unesco, the UN cultural body, approved Cambodia's application to have the complex named a World Heritage site.

Thai activists say the status undermines Thailand's claim to the compound of a nearby Buddhist pagoda.