Cambodia Launches UN Conciliation Over $300 Billion Maritime Dispute

On June 2, 2026, Hun Manet, Prime Minister of Cambodia, formally notified Thailand and the United Nations Secretary-General of the initiation of compulsory conciliation proceedings under the United Nations Convention on the Law of the Sea (UNCLOS). The move aims to resolve a maritime boundary dispute over 26,000 square kilometers in the Gulf of Thailand, an area estimated to hold oil and natural gas reserves valued at $300 billion.

This legal action follows a decision by the Thai cabinet on May 5 to unilaterally terminate a 2001 Memorandum of Understanding (MoU 44) that had served as the bilateral framework for negotiations for 25 years. Thai Prime Minister Anutin Charnvirakul, who scrapped the pact as part of an election pledge, argued the agreement had produced no results. The regional tension follows deadly military clashes along the land border in 2025 that killed nearly 150 people.

Cambodia has appointed Foreign Minister Prak Sokhonn as its agent and nominated Peter Taksøe-Jensen and Jean-Marc Thouvenin as conciliators. Thailand has 21 days to appoint two representatives to the commission. While Anutin Charnvirakul initially stated he was unaware of the filing, he later indicated Thailand would utilize UNCLOS principles. Thai Deputy Prime Minister Sihasak Phuangketkeow argued that bilateral talks would be more effective and warned that Cambodia's shift to an international mechanism could stall trust-building and border security efforts.