On 2 June 2026, Prime Minister Hun Manet announced that Cambodia had formally notified Thailand and the United Nations Secretary-General to begin compulsory conciliation under the United Nations Convention on the Law of the Sea (UNCLOS) over the Overlapping Claims Area in the Gulf of Thailand.
Cambodia’s move came after Thailand announced last month that it was withdrawing from the 2001 Memorandum of Understanding, the only bilateral framework that had guided maritime negotiations between the two countries for around 25 years.
Later, Thai Prime Minister and Interior Minister Anutin Charnvirakul said he had not yet been informed about Cambodia’s filing to the United Nations following Thailand’s unilateral cancellation of the 2001 MoU. He said Thailand would proceed in accordance with UNCLOS, but did not specify when or how Thailand would respond.
At the same time, Cambodian Deputy Prime Minister and Minister of Foreign Affairs and International Cooperation Prak Sokhonn told diplomats in Phnom Penh that Cambodia had already selected its two conciliators, while Thailand now has three weeks to appoint two conciliators of its own. This shows that Cambodia has already sent formal notification to both Thailand and the UN Secretary-General.
Prime Minister Anutin was also asked why Thailand needed to “counter-game” Cambodia’s move. In this regard, if Cambodia’s statement is correct, Thailand’s most immediate “counter-game” is not rhetoric, but procedure: it must appoint two conciliators within 21 days, or three weeks.
But what happens if Thailand does not appoint its two conciliators?
Under Annex V of UNCLOS, if one party fails to appoint its conciliators within the required period, the other party may ask the UN Secretary-General to make the appointments. The Secretary-General must then make those appointments within 30 days of receiving the request.
Another possible scenario is delay through legal objection. Thailand may later challenge whether the conciliation commission has jurisdiction or competence to hear the case.
The compulsory conciliation process is sensitive in Thai domestic politics. For years, Thailand has preferred bilateral negotiation with Cambodia rather than international courts or outside mechanisms. This is partly a legal strategy, but it is also domestic politics. Bilateral talks allow the Thai government to control the pace, wording, and public messaging of the dispute.
Anutin’s political position also matters. The cancellation of the 2001 MoU became part of his political messaging after border tensions with Cambodia, at a time when nationalist sentiment was rising in Thailand.
Thailand has long claimed areas such as Koh Kood as Thai territory. On 12 May, Sihasak Phuangketkeow also reinforced Thailand’s position by insisting that Koh Kut is clearly Thai territory when questioned about UNCLOS. The disputed maritime area is also believed to contain major oil and gas resources, with some estimates placing its value as high as $300 billion. For years, Thailand has had a strategic advantage by keeping the issue within a bilateral negotiation framework.
However, by triggering the withdrawal from the MoU for domestic nationalist reasons, the Anutin government may have opened the door for Cambodia to internationalize the issue through compulsory conciliation. This could raise deeper legal questions about maritime boundaries, overlapping claims, and whether some disputed areas should be treated differently under international law.