Thailand Prioritizes Bilateral Talks With Cambodia On Maritime Boundary Dispute

BANGKOK, Thailand — Thailand has reaffirmed its preference for direct bilateral negotiations with Cambodia to resolve their long-standing maritime boundary dispute in the Gulf of Thailand, emphasizing the use of the United Nations Convention on the Law of the Sea (UNCLOS) as a guiding framework before considering third-party intervention or formal dispute resolution mechanisms.

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Foreign Minister Siharak Phuangketkeow, who also serves as Deputy Prime Minister, stated on Monday that both nations should first endeavor to settle their overlapping maritime claims through direct dialogue, utilizing UNCLOS principles as a foundation, before progressing to other processes outlined in the treaty. His remarks came in response to recent Cambodian media reports suggesting that both countries had expressed favor for employing compulsory conciliation under UNCLOS to address their maritime differences.

The diplomatic exchange follows a meeting between Thai Prime Minister Anutin Charnvirakul and Cambodian Prime Minister Hun Manet on the sidelines of the Association of Southeast Asian Nations (ASEAN) summit in Cebu, Philippines, last Thursday. According to Cambodia’s Fresh News outlet, the two leaders discussed future approaches to managing their overlapping maritime claims during the trilateral session arranged by Philippine President Ferdinand Marcos Jr., who currently chairs ASEAN.

However, Foreign Minister Siharak clarified that no formal decisions regarding border matters were reached during the Cebu meeting. “The discussion was exploratory in nature,” he explained. “Both leaders acknowledged the importance of the issue but emphasized the need for continued dialogue and mutual understanding before advancing to specific procedural commitments.”

The maritime boundary dispute centers on an approximately 26,000-square-kilometer area in the Gulf of Thailand believed to contain significant reserves of oil and natural gas. The overlapping claims have remained unresolved for decades, with both nations conducting periodic technical discussions without achieving a final delimitation agreement.

Complicating the diplomatic landscape is Thailand’s recent decision to unilaterally withdraw from a 2001 Memorandum of Understanding that had served as the primary framework for managing the overlapping claims. Bangkok has argued that the MoU, after more than two decades, has failed to produce tangible progress and has at times exacerbated rather than eased bilateral tensions.

Cambodia, for its part, has formally notified Thailand of its intention to invoke the compulsory conciliation mechanism under UNCLOS—a process that would establish an independent panel of conciliators to facilitate resolution of the dispute. Under UNCLOS provisions, compulsory conciliation can be initiated by one party when bilateral negotiations have stalled, though the resulting recommendations are not legally binding unless both parties agree to accept them.

Foreign Minister Siharak expressed skepticism about Cambodia’s readiness to engage constructively on both maritime and land boundary issues. “Before we can meaningfully advance negotiations, both countries must rebuild mutual trust and demonstrate openness to compromise,” he stated. “Procedural mechanisms are important, but they cannot substitute for genuine political will and good-faith engagement.”

The foreign minister’s comments reflect Thailand’s broader diplomatic approach, which has traditionally favored direct negotiation and regional consensus-building over formal international adjudication. Thai officials have emphasized that bilateral dialogue allows for greater flexibility, cultural sensitivity, and attention to the specific historical and geographical contexts that shape the dispute.

Thailand has announced a clear stance on the issue of the overlapping sea boundary with Cambodia, placing priority on bilateral negotiations under the UN framework before bringing in outsiders to help settle the dispute.

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Legal experts note that UNCLOS offers multiple pathways for dispute resolution, including negotiation, mediation, conciliation, arbitration, and submission to the International Tribunal for the Law of the Sea. Thailand’s preference for the initial stages of this spectrum—negotiation and mediation—aligns with its historical practice in managing regional territorial and maritime issues.

“Thailand’s position is not about avoiding resolution; it’s about choosing the most appropriate path given the relationship between the parties and the nature of the dispute,” said a Bangkok-based international law scholar who requested anonymity. “Compulsory conciliation has its place, but it works best when both sides are already committed to implementing its outcomes.”

Cambodian officials have not issued a detailed public response to Foreign Minister Siharak’s latest remarks. However, previous statements from Phnom Penh have emphasized Cambodia’s commitment to peaceful dispute resolution through established international legal frameworks, while expressing disappointment at Thailand’s unilateral withdrawal from the 2001 MoU.

The dispute carries significant economic implications for both nations. The Gulf of Thailand area in question is believed to hold substantial hydrocarbon resources that could contribute to energy security and economic development for both countries. However, exploration and development activities have remained limited due to the unresolved sovereignty question, creating a “resource deadlock” that neither side has been able to break.

Regional observers note that maritime disputes in Southeast Asia often have implications beyond the immediate parties, affecting ASEAN cohesion, investment confidence, and broader geopolitical dynamics. The Thailand-Cambodia case is being watched as a test of whether neighboring states can manage complex boundary issues through dialogue while maintaining stable bilateral relations.

For now, both governments appear committed to keeping diplomatic channels open despite their differing preferences on procedural approaches. ASEAN, which emphasizes consensus-based diplomacy and non-interference, may play a facilitative role in encouraging continued dialogue, though the organization typically avoids direct involvement in bilateral boundary disputes.

“No one benefits from prolonged uncertainty,” said a regional diplomacy analyst. “Both Thailand and Cambodia have strong incentives to find a workable solution. The question is not whether they will resolve this, but how—and on what timeline.”

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As discussions continue, authorities on both sides have appealed to the public and media to exercise restraint in commentary on the issue, emphasizing that boundary negotiations require patience, technical expertise, and diplomatic discretion. Further official announcements regarding next steps in the dispute are expected as consultations between Thai and Cambodian officials proceed.

-Thailand News (TN)