Officials survey historical structures in Si Thep Historical Park in Phetchabun's Si Thep district. The government is pushing for the park to be recognised as a Unesco World Heritage Site. (File photo by Sunthorn Kongwarakom)

Residents in Phetchabun province who oppose oil exploration near an ancient historical site can breathe a sigh of relief after the cabinet approved a proposal to push for Si Thep Historical Park to be granted Unesco World Heritage Site status.

Last Tuesday, the cabinet also approved Phanom Rung Historical Park in Buri Ram province to be registered as such.

Thai delegates will present the registration application for the two sites at a Unesco meeting in Azerbaijan in June, according to Cultural Minister Veera Rojpojanarat.

The approval process is likely to take two years, and Thailand can place both sites on the "Tentative List" until their status is confirmed.

This cabinet approval has emboldened those who protested against planned oil exploration 100 metres from the 1000-year-old Si Thep Historical Park.

"We are getting closer to the day we can call Si Thep Historical Park a Unesco World Heritage Site when oil exploration near the area will be unthinkable," said Wisarn Kositanont, president of Cultural Council of Phetchabun province.

Eco Orient Resources was granted concessions to explore oil drilling in Si Thep district 15 years ago. The site, known as STN-2, is close to the ancient Khao Klang Nok stupa.

On March 28, after local resistance, Nawin Pantham, a company representative, announced at a meeting with the provincial governor that the plans had been dropped.

Yet local people remained concerned the company might still continue to explore for oil in other nearby areas that might also affect the historical site.

Critics said the only sure way to curtail oil exploration around the park was for the Fine Arts Department to announce the area within a 5-kilometre radius as a historical site.

Famous activist and president of the Stop Global Warming Association Srisuwan Janya submitted this petition to the department in March.

The ancient city in the park lies in an area that made it a historically essential "point of contact" between the Central Plains and the Northeast. It combines a mixture of the Buddhism-based culture of the Dvaravati kingdom and Khmer culture which draws on Hinduism and Mahayana Buddhism. Some of the buildings date back 2,500 years.

Sri Thep craftsmen benefited from these influences and went on to develop their own unique style, influenced by both cultures.

According to officials, the site falls under two criteria required by Unesco for the special designation. The first is that it is situated on a key corridor through which Southeast Asian culture spread. The second is that it demonstrates different cultures coming together to create new forms of artistic and architectural expression.

Meanwhile, Phanom Rung was constructed in the Angkor style between the 10th and 13th century. It consists of three main ancient structures.

One is the Phanom Rung sandstone castle located on the top of an extinct volcano in the Phanom Dong Rak Mountain Range. It was dedicated to the Hindu god Shiva.

Another is Muang Tum, a uniquely-styled castle about four kilometres southeast of Phanom Rung castle and built as a shrine for the Hindu Shaivism sect.

The last is Prasat Hin Khao Plai Bat I and II, which sit on Plai Bat Mountain, where the extinguished volcano lies.