Cambodia Reaffirms Border Stance, Defends UNCLOS Move in Dispute with Thailand

PHNOM PENH, June 5, 2026 (KPT ) – Cambodia on Friday reiterated its firm position on the Cambodia–Thailand border and defended its decision to pursue United Nations dispute-resolution procedures after Thailand withdrew from a long-standing bilateral framework on maritime claims.

Government spokesperson Pen Bona said Cambodia remained committed to safeguarding the international boundary as established by the Franco-Siamese Boundary Commission.

He stressed that the country’s stance was rooted in international law, citing the principle of uti possidetis juris, which upholds inherited borders, as well as Franco-Siamese treaties, official maps, demarcation records and agreements previously accepted by both sides.

“Cambodia absolutely does not recognize any alteration of the border resulting from the use of force,” Bona declared.

He explained that Cambodia’s decision to initiate the Compulsory Conciliation mechanism under the United Nations Convention on the Law of the Sea (UNCLOS) was intended as a legal and peaceful avenue to address maritime disputes.

According to Bona, Prime Minister Hun Manet had urged Thailand to reconsider its withdrawal from the 2001 Memorandum of Understanding (MoU), which had provided the sole framework for discussions on overlapping maritime claims for more than 25 years. Bangkok nevertheless proceeded, rendering the agreement void.

“The termination of the MoU shows that opportunities for resolution through bilateral negotiations have been exhausted,” Bona said, adding that the government had carefully assessed all legal and peaceful options before invoking UNCLOS procedures.

He noted that the move had garnered support from state institutions, ministries, government agencies, local authorities and citizens nationwide.