Cambodia has asked France to share historical documents and maps to help settle a long-running border dispute with Thailand that has sparked deadly clashes in the past year. Cambodian Prime Minister Hun Manet believes France’s records could offer reliable evidence of the original boundary, which France first drew when Cambodia was under colonial rule.
The request was made in a letter to French President Emmanuel Macron, asking for access to historical and technical documents related to the 817-kilometer (508-mile) border drawn in 1907 by French surveyors. France’s colonial mapping was based on a natural watershed dividing Cambodia from what was then Siam (now Thailand).
The territory near the 11th-century Hindu temple Preah Vihear, known in Thailand as Khao Phra Viharn, has been a major point of dispute. Both Cambodia and Thailand claim rights to the area, and the issue has fueled repeated tensions and violence over the decades.
The border conflict flared into fightings twice in 2025. In July, weeks of rising tensions after a soldier’s death led to five days of clashes that killed 43 people before a fragile ceasefire was arranged in Malaysia with outside diplomatic help. Fighting resumed later in the year and continued for more than three weeks, resulting in at least 101 deaths and displacing more than 500,000 people on both sides before a new ceasefire was declared on December 27, 2025.
Cambodia is also asking France for advisory support, saying it welcomes any expert guidance France can provide. Hun Manet noted that Macron had already indicated his willingness to help in earlier meetings. Both the French Embassy in Cambodia and the Thai foreign ministry had not yet commented publicly on the request.
The appeal highlights how colonial-era boundaries still influence modern disputes in Southeast Asia. France’s maps from a century ago are seen as one of the key historical records that could clarify where the official border should lie.
Border disagreements between Cambodia and Thailand are rooted in treaties from 1904 and 1907, when France negotiated with Siam to define their shared frontier. Over time, slight differences in map details and interpretation have led to persistent conflict, particularly around cultural and historical sites such as Preah Vihear.
By involving France, Cambodia hopes to bring neutral historical evidence into diplomatic talks and reduce tensions that have repeatedly turned violent.
