Recent clashes between Thai and Cambodian forces along their disputed border have subsided following five days of deadly confrontations in July, though underlying tensions persist in the region. The
Association of Southeast Asian Nations (ASEAN) is seeking to cement a more comprehensive ceasefire agreement during its upcoming summit in Kuala Lumpur on October 26, which U.S. President Donald Trump is expected to attend.
The situation remains delicate in Thailand’s Sa Kaeo province, where Cambodian residents have defied evacuation orders from two contested villages – Ban Nong Ya Kaeo and Ban Nong Chan. These locations, where Thai forces previously dismantled Cambodian checkpoints, are now secured with razor wire fencing and surveillance equipment, though Thai military officials have not forcibly removed the inhabitants.
The border dispute’s roots extend to the early 20th century, when French and Siamese surveyors created boundary maps in 1904 based on watershed areas. Thailand, then known as Siam, accepted these delineations and even incorporated French mapping during King Vajiravudh’s reign. A significant legal precedent was set in the 1960s when Cambodia successfully petitioned the International Court of Justice regarding the Preah Vihear temple dispute, an outcome that has made Thailand reluctant to pursue international arbitration since.
The 817-kilometer border remains partially undefined, with several historical markers either missing or disputed. Particularly
problematic is the Ta Phraya district, where only markers 32 and 37 have agreed-upon positions, while markers 33 through 36 remain contested and one marker is entirely absent.
Technical challenges further complicate the situation, as both nations employ different mapping scales – Thailand uses 1:50,000 while Cambodia relies on 1:200,000. According to historian Thongchai Winichakul, these incompatible methodologies mean even minimal discrepancies can translate to kilometers of disputed territory.
The Royal Thai Army maintains that their mapping approach provides superior accuracy, with spokesperson Maj. Gen. Winthai Suwaree citing aerial photography as evidence. He also noted the recent demographic shifts in the region, emphasizing the need for stricter border management.
The primary trade crossing between Aranyaprathet and Poipet, which closed during the July conflicts, is expected to remain shuttered through the end of the year.
Former Thai foreign minister Tej Bunnag has advocated for scientific border demarcation from the Gulf of Thailand to Ubon Ratchathani, suggesting that resolving boundary issues in Trat province could facilitate negotiations over offshore natural gas resources, similar to Thailand’s arrangement with Malaysia.
However, rising nationalist sentiments and political sensitivities have stalled progress on border resolution. Expert Thongchai suggests that maintaining the status quo might be the most practical approach, noting that while technical solutions exist, political obstacles remain insurmountable. He observes that many border committees have adopted this wait-and-see strategy, acknowledging that scientific solutions cannot overcome political deadlock.
The ongoing situation highlights the complex interplay between historical claims, technical challenges, and political realities in resolving long-standing territorial disputes in Southeast Asia.