Cambodia and Thailand kick off maritime conciliation in Singapore with a fiery start

A conciliation meeting between Thailand and Cambodia concerning overlapping maritime claims got off to a fiery start in Singapore on Sept 15 when Thailand’s Foreign Minister accused its neighbour of making claims that are “self-serving and contain elements of hypocrisy”.

This was as Cambodian Foreign Minister Prak Sokhonn positioned the meeting, which his country initiated, as “a peaceful pathway” forward in accordance with international law, after Thailand had cancelled an earlier agreement on the overlapping claims.

In a strongly worded speech, Thai Foreign Minister Sihasak Phuangketkeow said “Cambodia has repeatedly vilified Thailand through false narratives” instead of engaging in bilateral dialogue.

“And it does this by playing the role of a victim with a sense of self-righteousness aimed at claiming the moral high ground,” he added.

“We should recall the events that precipitated the conflict – when Cambodia led a private telephone conversation between our leaders, when Cambodian rockets hit and killed innocent Thai civilians, and when our soldiers lost their legs to landmines planted by Cambodia, where was respect for international law?”

Both ministers were giving their opening addresses to the Conciliation Commission established under the United Nations Convention on the Law of the Sea (UNCLOS).

They were allotted 15 minutes each at this first meeting, from Sept 14 to 16, at the Singapore office of the Permanent Court of Arbitration (PCA).

The compulsory conciliation, likely to take up to one year, is not a legal judgment and the final decision is non-binding.

However, analysts told The Straits Times they are hopeful that both countries can now find a way forward with the help of the commission.

Compulsory conciliation in 2016 – the only other time it was invoked – helped to break a diplomatic deadlock between Timor-Leste and Australia, which led to a historic maritime boundary treaty in 2018.

Prak, who spoke first at the meeting, opened his address with an overview of Cambodian history and noted that Phnom Penh had initiated this compulsory conciliation under UNCLOS after Bangkok cancelled a 2001 agreement on maritime cooperation and overlapping claims.

“Cambodia took this step to find a peaceful pathway forward in accordance with international law. Cambodia sees this conciliation process as a means to rebuild trust, not as a form of escalation,” said Prak, who is also Deputy Prime Minister.

The 2001 memorandum of understanding (MOU) concerns about 26,000 sq km of sea between the two countries, and this dispute has lasted for more than 50 years.

The contentious location is believed to hold almost 340 billion cubic m of natural gas and large quantities of oil worth about US$300 billion (S$382 billion). The MOU was meant to guide negotiations on overlapping maritime disputes and explore joint development plans for the resource-rich offshore areas.

In July 2025, clashes reignited between the two countries as they blamed each other for starting the fight at a separate disputed land border. These clashes have ceased temporarily, but tensions remain high.

Prak said he hopes the conciliation will lead to a maritime boundary delimitation treaty with Thailand or an agreement with Bangkok for the “joint development and equitable sharing of resources between the two states”.

“If a final agreement on either a maritime boundary or a joint development arrangement cannot be concluded, Cambodia would request the commission to prepare a report containing recommendations to the parties,” he added.

Taking a hard line

Sihasak, however, challenged Cambodia’s portrayal of the events leading up to the conciliation.

“Cambodia suggests that Thailand’s decision to terminate the MOU left it with no option but to initiate these proceedings. This is simply not true,” said Sihasak, who is also Deputy Prime Minister. “The truth is that over a period of 25 years, we managed to hold only two rounds of official talks.”

He said he had personally proposed to Prak that their countries begin direct talks on maritime boundaries and that they should proceed to conciliation together if no agreement emerged within six months – options that Cambodia had “disregarded”.

“So, for Cambodia to claim that it had no other option but to initiate these proceedings after Thailand terminated the MOU was an outright distortion of the facts,” Sihasak said.

Yet, it may be more prudent for smaller countries like Cambodia to rely on international arbitration mechanisms to resolve conflict, said Hunter Marston, director of the South-east Asia programme at the Lowy Institute.

“Thailand, the larger power, would rather avoid international arbitration, but compulsory conciliation has forced its hand. The legal mechanism balances the scales by giving the smaller power a greater voice and resources to resolve the dispute,” he added.

At the meeting, Prak said he hopes the conciliation will bring benefits for both nations.

“Cambodia and Thailand’s relationship has been through a challenging period, and Cambodia hopes that the commission may be able to help the parties turn a new page for their mutual benefit,” he said.

Sihasak maintained that the door for dialogue with Cambodia remains open.

“Thailand stands ready to engage in this process constructively, with the aim of achieving, with the commission’s assistance, a negotiated and equitable solution. Conciliation can help the parties to identify common ground, narrow divergent legal positions and negotiate a way forward,” he said.

However, he drew the line at Koh Kood, an island in south-east Thailand, reiterating that it belongs to Bangkok and that the conciliation process should not concern “sovereignty over land”.

“There has never been a debate on this matter. Thailand rejects Cambodia’s 1972 continental shelf claim line, which is without legal basis,” he said.

Marston said it is unclear if these statements will have any impact on the PCA’s decision.

“Thailand is taking a bit of a hard line by attempting to limit the court’s remit to boundary delimitation and portraying Cambodia as acting in bad faith, while Phnom Penh struck a more conciliatory tone and left the court’s purview open,” he noted.

Thailand’s sharp comments have “already generated some online media attention and reactions”, said Deth Sok Udom, a professor of international relations at Paragon International University in Cambodia.

Cambodian netizens flooded social media with posts slamming Sihasak’s biting comments, accusing Bangkok of invading Cambodian territory.

Thai netizens hit back, defending Sihasak’s resolute stance while blaming the Cambodians for “distorting” the truth.

“The continued closed-door discussions could help address some technical matters, but any prospect for agreed demarcation appears dim from the outset, while any resource development framework conditional upon official demarcation would be complicated and politically sensitive for nationalists on both sides,” Deth added.

Conciliation buffers tense bilateral relations

Despite the squabble, analysts told ST they are optimistic that Thailand and Cambodia can resolve their differences through the commission, which comprises legal experts chosen by both countries.

“The fact that they are sitting together in a legal framework with conciliators that they have consensus on, instead of resorting to public displays of retaliation, reaction and unilateralism, is a good thing in and of itself,” said William Jones, an international relations assistant professor at Thailand’s Mahidol University International College.

Agreeing with this view, Paragon International University’s Deth called the process “pragmatic”.

“At the very least, the process will offer the parties more time and a mediated venue to discuss potential cooperation that could yield a win-win framework,” he said.

Jones believes the commission also wants to help the two come to a peaceful settlement.

“They have a vested interest in making conciliation work as an international example as well as pragmatically avoiding conflict between the states” he said.

“Thailand will accept the proposal of the committee as it’s not an outlaw nation (but) this doesn’t mean they will follow through with it,” he added.

Though some analysts have not placed much significance on the location of the inaugural meeting, Marston believes Singapore is an ideal site for neutrality.

The city-state will also take over as ASEAN chair in 2027, when the dispute between Thailand and Cambodia will most likely be a topic of discussion among the 11-member grouping.

“This will allow Singapore to exercise more continuity and leadership in the process and manage the dispute going into 2027,” Marston said.

ST understands that future conciliation meetings may take place in other PCA offices, based on scheduling and the convenience of all parties involved.

The PCA, which is headquartered in The Hague in the Netherlands, has offices in countries like Argentina, Austria and Vietnam.