Cambodia complained to the U.N. Security Council that Thai forces have violated its territory near a World Heritage Site temple, as more than 4,000 troops from the two sides were deployed in the border region Sunday.

The two countries were to hold talks Monday in Thailand aimed at resolving the dispute, but a Cambodian general said he had little hope they would succeed.

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Cambodia's mission at the United Nations submitted a letter to the chairman of the Security Council and the chairman of the General Assembly to "draw their attention to the current situation on the Cambodian-Thai border," Information Minister Khieu Kanharith said Sunday.

"Cambodia is not asking for U.N. intervention. We still stick to Prime Minister Hun Sen's instructions to try to solve the problem peacefully between the two sides," the minister said.

The conflict over territory surrounding the ancient Preah Vihear Hindu temple escalated when UNESCO recently approved Cambodia's application to have the complex named a World Heritage Site. Thai activists say the new status will undermine Thailand's claim to nearby land.

The tension, which began Tuesday, is centered on the compound of a Buddhist temple near the Preah Vihear temple complex. Cambodia and Thailand both claim the compound.

In his letter Friday to the Security Council, Cambodian U.N. Ambassador Sea Kosal said the action by Thai troops was aimed at creating "a de facto overlapping area that legally does not exist on Cambodian soil." A copy of the letter was obtained by The Associated Press on Sunday.

Based on estimates by commanders and AP reporters on both sides of the border, more than 4,000 troops have been deployed around the temple and in the immediate border region.

Reporters saw at least nine Thai military trucks hauling small artillery pieces and soldiers toward the disputed area Sunday, but the atmosphere appeared relaxed despite the close proximity of the two forces.

Opposing commanders and their troops have tried to defuse tensions, sometimes even sharing meals, snapping photographs and sleeping within easy sight of each other.

"Some of these soldiers [the Cambodians and the Thais] have known one another a long time and they have good relationships. The soldiers on both sides understand each other," Thai field commander Col. Chayan Huaysoongnern told reporters.

A Cambodian general, however, said he had little hope that the talks Monday between his government and Thailand would resolve the matter.

Cambodian Brig. Gen. Chea Keo said Thai troops have deployed artillery about half a mile northeast of Preah Vihear temple.

"Regarding the talks tomorrow, we have little hope about the outcome," Chea Keo said.

He said the reason for his pessimism stems from a recent counterclaim by Thai Prime Minister Samak Sundaravej that the area around the Buddhist temple belongs to Thailand.

While urging both sides to exercise restraint, Samak's letter said a settlement of Cambodians in that area constitutes "a continued violation of Thailand's sovereignty and territorial integrity."

Maj. Gen. Weewalit Jornsamrit, a senior Thai commander at the border, said an estimated 1,300 Cambodian troops were deployed in and around Preah Vihear.

Weewalit declined to give Thai troop numbers but a senior Thai officer, who spoke on condition of anonymity because of the sensitive situation, said about 2,600 soldiers were in the Thai district opposite the border. About 400 were seen in the disputed area.

"We continue to be on alert at all times. And at the same time, we keep instructing our soldiers to be patient and avoid being blamed for starting a war," Chea Keo said Sunday.

The dispute has taken a toll on tourism in the area, with the Thai side closed to visitors. It also is starting to hurt economic relations between the two neighbors.