Asian AngleCambodia and Thailand must define the border to achieve lasting peace

The Cambodia-Thailand border dispute is complex: the result of a tangle of colonial-era treaties, competing maps, contested temples, unsettled demarcation and recurring nationalism. The rise of ultranationalist groups on both sides has made reconciliation harder still. Armed clashes, partly driven by domestic political developments, erupted in July and December 2025, showing how quickly the dispute can turn violent and how costly that violence can be for both economies.

From Phnom Penh’s perspective, the immediate priority is pressing Thailand to withdraw its troops while rejecting attempts to redraw borders through force, coercion or fait accompli. Cambodia’s approach rests on three tracks: bilateral mechanisms, international legal processes and third-party mediation. For any of these to deliver results, however, both sides must first settle demarcation itself.

1. Bilateral negotiation. The first track runs through existing mechanisms. These include the Joint Boundary Commission (JBC), established in 2000 under a memorandum of understanding on land boundary survey and demarcation. The JBC is the main technical body for survey, mapping and demarcation, working alongside the General Border Committee on security and military matters and the Regional Border Committee on local incidents.

In April, Prime Minister Hun Manet stated that “even if only 1 per cent” of diplomatic opportunity remained, Cambodia was “committed to fully exhausting all peaceful mechanisms rather than resorting to prolonged conflict”. Existing mechanisms are often slow-moving and constrained by domestic political pressures, yet they remain indispensable for confidence-building, preventive diplomacy and the pursuit of practical technical solutions.