PHNOM PENH / BANGKOK - Cambodian and Thai troops clashed briefly on Monday for a fourth straight day, Phnom Penh officials said, as UN chief Ban Ki-moon called for "maximum restraint" in a border dispute that has claimed six lives.

The latest flare-up erupted during an operation by Thai soldiers to recover casualties from Sunday's heavy fighting, according to Cambodian officials, who accused Thailand of damaging an 11th-century temple at the center of the hostilities.

Thai villagers pray at a shelter in Si Sa Ket province after fleeing the area near the 11th-century Preah Vihear temple at the border between Thailand and Cambodia Feb 7, 2011. [Photo/Agencies]

The officials said one Cambodian soldier was killed overnight and accused Thailand of wanting to occupy the disputed 4.6-square-kilometer area around the Preah Vihear temple.

Thailand, however, played down the latest skirmish, with a military source near the border describing it as a "misunderstanding".

The renewed clashes - which were reported to have injured 13 Thai soldiers on Sunday - shattered a brief cease-fire agreed on Saturday after the worst fighting between the two nations in years.

In New York, Ban's office issued a statement saying the UN chief was "deeply concerned" about the standoff.

"The secretary-general appeals to both sides to put in place an effective arrangement for cessation of hostilities and to exercise maximum restraint," it said.

China also called for calm and restraint from Cambodia and Thailand.

"Both Cambodia and Thailand are China's friendly neighbors. China hopes that the two nations exercise calm and restraint, resolve disputes through consultation, and prevent the situation from escalating," Foreign Ministry spokesman Hong Lei said on Monday.

Sombo Manara, a history professor at the Royal University of Phnom Penh, said long-standing disagreement over the countries' border was behind the dispute.

"I don't think that the conflict will end without intervention from a third party and clear demarcation (of the border) between the two countries," he said.

A joint commission on border demarcation between Thailand and Cambodia plans to meet later this month, a senior Thai official said on Monday.

The Thai-Cambodian Joint Commission on Demarcation for Land Boundary, led by senior government officials of both countries, is scheduled to meet late February, Chavanond Intarakomalyasut, secretary to Thai foreign minister, told a local television.

The Association of Southeast Asian Nations (ASEAN) urged Thailand and Cambodia on Monday to return to the negotiating table.

Surin Pitsuwan, secretary-general of ASEAN, said that the deteriorating situation along the Thai-Cambodian border is undermining confidence in ASEAN and affecting economic recovery, tourism and investment prospects in the region.

AFP-Xinhua