PHNOM PENH (AFP) - Thailand and Cambodia showed no signs Tuesday of resolving their long-simmering spat over a disputed border area near an ancient temple, with Bangkok insisting its troops would remain in place. Thailand's statements came after an ultimatum from Cambodia to withdraw from the territory near the Preah Vihear temple, a UN World Heritage site, or run the risk of "large-scale armed conflict". Early Tuesday, Cambodian officials said the Thai troops had left their positions near the centuries-old Khmer site, but Thai officials told reporters they had not budged " and would not any time soon. "All 80 troops will remain in the disputed area because Thailand has overseen that area for 20 to 30 years," Foreign Minister Sompong Amornviwat said, a day after returning from talks in Phnom Penh with his opposite. "Of those 80 troops, 20 of them are mine clearance workers and the rest offer protection for the mine clearance troops. Thailand insists it has not encroached in any territory." After meeting Thailand's military top brass to discuss the tensions, Thai Prime Minister Somchai Wongsawat also said troops would remain in the border area, but pledged to avoid confrontation and focus on talks. "The Thai stance is that we adhere to peaceful co-existence and we will not be first to start aggression," he said. But Cambodia's foreign ministry and military, as well as witnesses in the contested territory, insisted that the Thai troops had withdrawn early Tuesday after commanders from both sides held talks. "They withdrew from the area around 10:20 am and went back to their headquarters, which is around a kilometre away," Cambodian Brigadier General Yim Pim told AFP by telephone from the area. "There is no more confrontation now. The situation is eased now, but we are still on high alert." The Thai army ratcheted up its rhetoric Tuesday, saying that it was prepared for a confrontation with Cambodia if the border dispute were to escalate. The tit-for-tat statements followed a Monday ultimatum from Cambodian Prime Minister Hun Sen, who warned that the soldiers had to pull back by midday (0500 GMT) or risk being caught in a battle zone. The Thai foreign ministry said that Hun Sen's statement ran "counter to the spirit of neighbourliness" and flouted a regional treaty on cooperation. "Thailand will have to exercise its right of self-defence" if Cambodia uses force, the foreign ministry said, adding it was investigating whether Phnom Penh had violated an international treaty by laying new landmines in the area. Tensions between the neighbours first flared in July after the temple was awarded World Heritage status by the United Nations cultural body UNESCO. The situation quickly escalated into a military confrontation, with up to 1,000 Cambodian and Thai troops facing off for six weeks, although both sides in August agreed to reduce troop numbers. The International Court of Justice ruled in 1962 that the temple belongs to Cambodia, but surrounding land remains in dispute, and each side accuses the other of violating its territorial sovereignty. Speaking at an economic forum in Phnom Penh on Tuesday before the reported withdrawal, Hun Sen maintained his tough rhetoric.