Full Breakdown
Thailand Ends 25-Year Maritime Cooperation Pact with Cambodia, Shifts to UNCLOS Framework
5/6/2026, 5:54:41 PM
Termination of the 2001 Maritime MOU
On 5 May 2026 Thailand’s cabinet voted to cancel the 2001 Memorandum of Understanding (MOU 44) that provided a bilateral framework for joint offshore energy exploration in the Gulf of Thailand. The decision, announced by Prime Minister Anutin Charnvirakul, will take legal effect only after Thailand sends a formal notification to Cambodia.
Background & Context
The MOU was signed in June 2001 to manage overlapping maritime claims and to allow joint development of oil and gas while parallel boundary negotiations continued. Over the past two decades only five formal negotiation rounds were held, producing no concrete outcomes. In July 2024 and December 2024 the two neighbours fought fierce border clashes along their 817-km land frontier, killing close to 150 people, displacing hundreds of thousands and prompting a fragile ceasefire in late December. The violence revived nationalist sentiment in Thailand and became a central issue in the 2025 election, which Anutin’s Bhumjaithai Party won.
Key Figures & Groups
- Anutin Charnvirakul – Thai Prime Minister; pledged to scrap the MOU as an election promise.
- Sihasak Phuangketkeow – Thai Foreign Minister; frames the shift to the United Nations Convention on the Law of the Sea (UNCLOS) as a “reset.”
- Rachada Dhnadirek – Thai government spokesperson; emphasizes the termination is an “adjustment of the framework for cooperation.”
- Prak Sokhonn – Cambodian Foreign Minister; expressed regret and announced compulsory conciliation under UNCLOS.
- Hun Manet – Cambodian Prime Minister; reiterated Cambodia’s commitment to peaceful, law-based resolution.
Timeline of Recent Developments
- 2001 – MOU 44 signed.
- 2024 Jul & Dec – Two rounds of armed clashes; ceasefire established late Dec.
- 2025 Mar – Anutin’s party includes MOU termination in its platform.
- 2026 May 5 – Thai cabinet votes to terminate; Cambodia announces UNCLOS conciliation.
Data & Statistics
- Casualties: reports vary between “several dozen” and “close to 150” deaths.
- Displacement: hundreds of thousands forced from border areas.
- Negotiations: five formal rounds since 2001; no joint hydrocarbon projects realized.
- Border length: 817 km (508 mi).
Why It Matters
The Gulf of Thailand holds significant offshore oil and gas potential. The MOU’s collapse removes the only bilateral mechanism for joint development, pushing both states toward a multilateral legal process that may delay resource exploitation. The move also signals a shift from cooperative engagement to unilateral assertion of sovereignty, with implications for regional stability and ASEAN cohesion.
Official Statements & Responses
Thailand’s spokesperson Rachada Dhnadirek described the termination as a “realignment” rather than a rupture of relations, noting future talks will rely on UNCLOS. Foreign Minister Sihasak Phuangketkeow said the change is intended to “allow negotiations to go forward” and that Thailand’s intentions are “sincere.” Cambodia’s Foreign Minister Prak Sokhonn called the decision a “departure from the spirit and political will” of the original framework and announced compulsory conciliation under UNCLOS, asserting that Cambodia’s lawful maritime rights remain unchanged. Prime Minister Hun Manet echoed this, saying Cambodia has “no choice but to rely on international law.”
Criticism & Opposition
Thai nationalist groups and “ultra-patriotic” factions have long opposed any perceived compromise over sovereignty, pressuring the government to abandon the MOU. Analysts note that the termination aligns with domestic political calculations as much as with the lack of progress on energy projects.
Conflicting Reports & Gaps
Sources differ on casualty figures (“several dozen” vs. “close to 150”) and on the exact number of negotiation rounds (five formal rounds cited, but some reports mention “five rounds” without specifying outcomes). No official data on the size of the disputed offshore reserves has been released.
Verbatim Quotes
- “Cancelling the deal is not related to the border conflict with Cambodia, but part of my policy. It has been 25 years and there has been no progress,” — Anutin Charnvirakul, Prime Minister of Thailand
- “Cambodia’s decision reflects our sincere hope that both countries can reach a just and lasting solution in line with international law, allowing our peoples to live together in peace, stability, and harmony.” — Hun Manet, Prime Minister of Cambodia
- “Cambodia’s decision to pursue compulsory conciliation under UNCLOS reaffirms its commitment to resolving maritime disputes peacefully and in accordance with international law,” — Prak Sokhonn, Cambodian Foreign Minister
- “We are very disappointed that the Thai side is considering unilaterally withdrawing from the MOU 2001,” — Kung Phoak, Secretary of State, Cambodian Ministry of Foreign Affairs
What’s Next
Cambodia plans to file a compulsory conciliation request under UNCLOS, a non-binding but legally structured dispute-resolution process. Both governments have indicated willingness to continue bilateral talks within the UNCLOS framework. The issue will feature at the ASEAN summit in Kuala Lumpur (6-8 May 2026), where regional leaders are expected to discuss mechanisms for managing overlapping maritime claims in resource-rich waters.
