
Director of Treaty and Legal Affairs, Virachai Plasai, told the ambassadors the area in question is "overlapping" and requires demarcation under a treaty signed by Thailand and Cambodia in 2000.
"We raised objections in line with international practices because we believe the map is incorrect," he says.
Thailand says the issue will not affect bilateral relations. The two countries have clashed previously over ownership of the Preah Vihear Hindu temple. Bangkok opposes Phnom Penh's plans to list it as a United Nation's World Heritage site before ownership is settled.