Thailand and Cambodia will dial down political rhetoric and focus on the legal aspects of their maritime disputes when they meet next month to seek an amicable solution under the UN-sponsored “compulsory conciliation” process.
Thai Foreign Minister Sihasak Phuangketkeow had delivered a tough opening statement in Singapore, which resonated with nationalist sentiment at home. Many Thai scholars, however, criticised it as an attempt to appeal to domestic audiences and bolster the government’s political standing, rather than presenting a coherent and persuasive case before the conciliation commission.
The government in Phnom Penh initiated the UN-backed compulsory conciliation proceedings following the unilateral decision by the Anutin Charnvirakul administration in May to scrap the 2001 Memorandum of Understanding on delimiting the maritime boundary and jointly developing hydrocarbon resources in the overlapping claims area of the continental shelf in the Gulf of Thailand.
The Thai termination of the MOU was a response to border tensions and two skirmishes between the two neighbors last year that caused large numbers of casualties, billions in economic losses for both countries, and displaced thousands of people.
In his opening statement, Sihasak used unusually strong language, describing Cambodia’s claims of respect for international law as “self-serving” and containing “elements of hypocrisy”.
The Thai minister invoked the leaked telephone conversation between the two countries’ leaders, Cambodian rocket attacks that killed Thai civilians, and landmine explosions due to which Thai soldiers lost their legs, before asking rhetorically: “Where was respect for international law?”
Sihasak ruffles a few feathers
In his article entitled “It May Feel Good, but It Won’t Win the Case”, Professor Surachart Bamrungsuk of Chulalogkorn University accused the foreign minister of clinging to Thai nationalist ideology since the 2025 border skirmish to boost political support for the government and also foster an image of himself as a nationalist minister.
“But 2026 should be a year of solving the problem and finding a way for Thailand to get out of Cambodia’s war trap, because this war has not provided a strategic return for Thailand and also severely impacted Thailand’s domestic economy,” he said.
Akkharaphong Khamkhun, a lecturer from Thammasat University, faulted Sihasak’s opening statement for misrepresenting the conciliation process as an arbitration or a court hearing in which the rival parties are expected to confront, discredit, and pin down the other side.
If one looks closely at the provisions of Article 298 of UNCLOS 1982, together with Annex V, particularly Articles 5 and 6 on Conciliation, it becomes immediately clear why the United Nations framework treats arbitration separately under Annex VII, he explains.
UNCLOS stands for the United Nations Convention on the Law of the Sea adopted in 1982 to govern maritime utilisation and dispute settlement.
Established under Annex V of the 1982 UNCLOS, compulsory conciliation is a non-binding dispute settlement mechanism designed primarily for complex maritime disputes, including maritime boundary delimitation, where states are unable to reach an agreement through direct negotiations.
This forum tasks five commissioners with facilitating an amicable settlement—that is, a friendly and mutually acceptable resolution of the dispute, Akkharaphong said.
The commissioners are not judges, nor are they an arbitral tribunal or arbitrators whose function is to adjudicate the dispute and render a legally binding determination designed to produce an equitable solution.
“It is rather like the difference between attending a funeral and attending a wedding. One should know what kind of occasion one is attending,” Akkharaphong said in his Facebook post, in his reaction to Sihasak’s statement.
“One’s attitude, mood and tone should be appropriate to the nature of the forum. One cannot walk into every forum with the sole intention of cutting the other side down to the ground.”
Sihasak defended his actions, telling a Thai PBS program that “in the opening round, we had to show some footwork and size up the other side. The next round will move on to the substance, focusing on technical issues and principles of international law”.
The road ahead
The five-member Conciliation Commission chaired by Australian diplomat Katrina Cooper did not pay attention to political rhetoric but focused only on the way forward.
In its press statement issued on September 16 after the Singapore session, it highlighted Sihasak’s words that conciliation could help the two parties to identify common ground, narrow divergent legal positions, and negotiate a way forward.
It quoted Sihasak as saying that Thailand had “entered this conciliation in good faith, fully mindful of the provisions of UNCLOS, and with confidence in the independence, impartiality, and collective expertise of this Commission”.
Looking ahead, Sihasak said that Thailand “stands ready to engage in this process constructively, with the aim of achieving, with the Commission’s assistance, a negotiated and equitable solution”.
The press release also highlighted similar sentiments expressed by Cambodia. It quoted Foreign Minister Prak Sokhonn as saying that “both Cambodia and Thailand stand to gain from a fair and lasting settlement agreed with the guidance of the international expert conciliators and in accordance with international law”.
It said that Prak Sokhonn further noted he regarded this conciliation process “as a means to rebuild trust, not as a form of escalation”.
Looking ahead, the Cambodian minister said that the “overriding objective” was to “achieve a resolution that serves the people of both nations and contributes to peace, cooperation, and shared prosperity in the region”.
The view from Phnom Penh
Cambodia, which initiated the compulsory conciliation, is seeking a “delimiting all-purpose maritime boundary” treaty with Thailand
“In the alternative, Cambodia would be prepared to conclude an agreement with Thailand for the joint development and equitable sharing of resources between the two states, pending the final agreement on their maritime boundary,” Prak Sokhonn said in his opening statement.
Thailand, according to Sihasak’s statement, said the scope of the proceedings concerned only maritime boundary delimitation and Bangkok reaffirmed its maritime boundary position as reflected in the Royal Proclamation of May 18, 1973.
“We seek nothing more than the protection of our sovereignty, sovereign rights and our legitimate entitlement under international law,” Sihasak said.
However, in an interview with local media, Sihasak did not rule out the possibility of a joint development scheme between Thailand and Cambodia, but that could happen only after the delimitation of the boundary.
“If we know the boundary line, we will know the overlapping areas and it would be easier to define the resource sharing scheme,” he said, noting that if both sides entered the conciliation process in good faith and true sincerity as good neighbors, solutions could be found.
“The UNCLOS conciliation process might be based on legal technicality, but as a diplomat I do believe we would have some room for diplomatic negotiations for good outcomes,” he said.
The overlapping continental shelf claims in the Gulf of Thailand, disputed by Thailand and Cambodia since the 1970s, cover approximately 26,000 square kilometers.
Studies suggest the area contains substantial energy reserves, including an estimated 11 trillion cubic feet of natural gas and 300–500 million barrels of crude oil, with a combined economic value of around US$300 billion.
The 2001 MOU signed during the Thaksin Shinawatra administration made no significant progress over the past 25 years due to political obstacles: right-wing nationalists accused Thaksin of having a conflict of interest due to his close ties with former prime minister Hun Sen of Cambodia. They consistently called for the termination of the MOU.
