Thailand has formally protested to Cambodia after a group of Cambodian women was filmed singing a nationalist song at a disputed Khmer temple in a sensitive border area.

The video, filmed at Prasat Ta Muen Thom in eastern Thailand, shows the women in traditional dress singing, “All Khmer people are happy to sacrifice their lives when the nation is at war and shedding blood.”

Thai soldiers guarding the temple then escorted the women away from the 11th-century structure, which lies directly on the border, to the Cambodian side.

Thailand's Deputy Prime Minister Phumtham Wechayachai said Monday he was “uncomfortable” with the incident and had sent a letter of protest.

"We are worried that history will repeat itself," he told reporters.

This was an apparent reference to the bloody military clashes that erupted some 15 years ago between Thailand and Cambodia over the Preah Vihear temple, which lies some 150 km (95 miles) east on the same stretch of border.

The row over a patch of land next to Preah Vihear led to several years of sporadic violence, resulting in at least 28 deaths before the International Court of Justice ruled the disputed area belonged to Cambodia.

A Thai task force responsible for the region issued a letter protesting against the actions of Cambodian tourists.

"This could affect international relations between the two countries," the Suranaree task force warned.

Prasat Ta Muen Thom was built by Jayavarman VII, king of the Khmer Empire that dominated the region from the 11th to 13th centuries.

The Cambodian government has yet to comment on the issue.