Cambodia Appeals to the United Nations to Resolve Maritime Border Dispute with Thailand

Cambodia has initiated the ‘mandatory arbitration process’ under international law to resolve its maritime border dispute with Thailand. The Thai government unilaterally annulled the 2001 border negotiation agreement between the two countries just last month. Following this, Cambodia took the step independently. Cambodian Prime Minister Hun Manet stated that this process was pursued to protect their sovereignty and maritime rights in accordance with international law, and that the United Nations and Bangkok have been informed about this development.

Meanwhile, Thailand’s Prime Minister Anutin Charnvirakul said he was not informed about Cambodia starting this procedure. During his election campaign in February, Prime Minister Anutin had made the annulment of the 2001 agreement a key issue, but he now acknowledges that Thailand has not yet decided how to proceed on the matter. Under the United Nations Convention on the Law of the Sea (UNCLOS), this mandatory arbitration process involves a panel of independent experts who will study the dispute and prepare recommendations. However, these recommendations will not be legally binding on either country.

The dispute concerns approximately 26,000 square kilometers in the Gulf of Thailand, known as the ‘Overlapping Claims Area’ (OCA). This region is estimated to contain around 12 trillion cubic feet of natural gas and substantial petroleum reserves, with a market value of about 30 billion US dollars. Given the global fuel shortages caused by the Iran crisis, resolving this dispute over valuable underground energy resources has become a critical priority for both nations.

Cambodia has appointed its Foreign Minister, Prak Sokhonn, as the chief agent in this legal process and selected Danish diplomat Peter Taksoe-Jensen and French expert Jean-Marc Thouvenin as arbitrators. Thailand is now required to appoint two arbitrators within 21 days. This commission, formed under the supervision of the UN Secretary-General, will proceed with the examination of the dispute.

Previously, Thailand had rejected Cambodia’s efforts to resolve the dispute through the International Court of Justice or other external mechanisms, insisting instead on bilateral negotiations. Last year, intense military clashes along the 817-kilometer land border resulted in more than 150 deaths and displaced hundreds of thousands. Since then, with mediation by US President Donald Trump, a ceasefire has been in place between the two countries since December.