Thailand’s new government has floated a national referendum on whether to revoke its two cornerstone agreements with Cambodia, the 2000 Memorandum of Understanding (MoU) on land-boundary survey and demarcation, and the 2001 MoU on the overlapping maritime claims area.
Thai Prime Minister Anutin Charnvirakul’s team has framed the idea as a reset after this year’s deadly flare-up along the frontier. But a referendum on complex legal instruments risks swapping technical problem-solving for symbolic politics with high stakes for Thai-Cambodian relations and ASEAN cohesion.
The timing is hardly accidental. In late September, Anutin announced he would seek a public vote on cancelling the MoUs, presenting it as part of a broader agenda to confront the border crisis and push constitutional reform. News wires quickly linked the move to the July 2025 fighting, five days of clashes that killed dozens, displaced hundreds of thousands, and required a ceasefire brokered in Malaysia along an 817-kilometre frontier that has long been fraught.
Domestically, the referendum lands in a volatile political moment. Anutin heads a minority coalition, recently installed after royal endorsement of his cabinet, with the progressive People’s Party pledging to act as a critical ally-opposition. A polarising border vote could galvanize nationalist sentiment and shore up a fragile parliamentary base, even as it complicates relations with the opposition and neighbours.
The politics of the poll are clear; public understanding is not. A new NIDA survey suggests a majority of respondents back holding a referendum to cancel the MoUs, but also reveals widespread confusion about what those documents actually do. One account reports about 60-61 per cent support for a referendum while significant shares roughly half to two-thirds depending on the question framing, admit limited comprehension of the content of the MoUs. That gap has already drawn warnings from Thai opposition figures about sending voters to decide on highly technical instruments without adequate public education.
What, precisely, would Thailand be scrapping? The 2000 MoU sets the procedural architecture for land-boundary survey and demarcation, joint commissions, technical work plans and coordination rules to translate maps and ground features into agreed border lines. It is not a final boundary treaty; it is the scaffolding for getting there.
The full text is publicly available, including via Cambodia’s official channels.
The 2001 MoU similarly creates a framework for negotiating the overlapping claims area of the continental shelf in the Gulf of Thailand; again, not a line on the map but a process to reach one.
These are quintessential “process instruments”. Their value lies in providing predictable, joint procedures through which technical experts can work, insulated, at least in theory, from political mood swings. Dismantling that scaffolding does not deliver a better line; it delivers no line, and fewer agreed rules to find one.
Would revocation be legally straightforward? Not exactly. Some MoUs in international practice are non-binding political arrangements; others, though labelled “MoU”, are binding intergovernmental agreements in substance and effect. The UN International Law Commission has cautioned against assuming form determines legal character, and scholars note that even non-binding MoUs can produce indirect legal effects by shaping treaty interpretation and diplomatic expectations.
If Thailand treats the 2000 and 2001 MoUs as treaties, the Vienna Convention on the Law of Treaties (VCLT) offers baseline guidance.
Termination or withdrawal typically occurs in conformity with the treaty’s own clauses or by consent of the parties; where no clause exists, unilateral denunciation is constrained unless the parties intended to allow it or a right of withdrawal can be implied.
Regardless, treaty law presumes good-faith performance (pacta sunt servanda) and disfavours steps that defeat an agreement’s object and purpose without a negotiated alternative. Those are demanding guardrails for a one-sided exit from procedural frameworks built for joint work.
If the government instead argues the MoUs are political and non-binding, revocation still carries costs.
First, it signals that Bangkok is prepared to politicise technical border management, undermining the credibility of future frameworks. Second, it opens a vacuum. Without agreed procedures, every survey mission, marker repair or maritime seismic campaign risks escalation. Third, it invites third-party fora possibly the International Court of Justice or arbitral bodies if one side seeks clarification or protection against unilateral moves. Even Thai voices have warned that scrapping the MoUs could boomerang into litigation and diplomatic isolation.
Proponents will argue that the July violence proves the frameworks failed. But that interpretation confuses cause and consequence. The land and maritime MoUs were designed to manage disputes and enable incremental progress; they are not guarantors against political crises or local provocations.
Revoking them would not fix grievances on either side about temple precincts, watershed lines, or shelves rich in hydrocarbons. It would instead remove safety rails that have despite setbacks structured two decades of joint work.
The referendum itself presents three practical problems.
First, it collapses complexity into a binary. Border demarcation is a slow, technical enterprise involving historical maps, ground-truthing, geodesy and painstaking joint minutes. A yes/no question cannot capture the trade-offs embedded in each river bend or ridge line. The NIDA findings underscore the risk of a mandate generated by sentiment rather than understanding.
Second, it risks locking in maximalist positions. A campaign will reward hardline rhetoric, not the quiet compromises technical teams need. Even if the government keeps the MoUs, the political cost of flexibility will rise after a nationalist plebiscite.
Third, it has externalities for ASEAN. The ASEAN Charter and the Treaty of Amity and Cooperation (TAC) codify regional norms: peaceful settlement, non-use of force and habits of consultation. Unilaterally detonating bilateral frameworks especially after deadly clashes cuts against that spirit and pressures ASEAN to choose between strict non-interference and its own commitment to de-escalation.
For Cambodia, the politics are immediate. Phnom Penh will see revocation as proof that Bangkok prefers domestic optics to problem-solving, and may harden its own posture on both land markers and the offshore “overlapping claims area”. The maritime file is especially sensitive because commercial interests (energy plays and fisheries) intersect with sovereignty narratives. Without the 2001 framework, the risk of unilateral licensing, patrol incidents, or tit-for-tat seizures grows.
What should Thailand do instead?
Keep the frameworks, fix the practice. The government could pair a pledge to maintain the MoUs with a time-bound overhaul of the joint machinery: transparent timelines for survey cycles, better dispute-prevention hotlines and a commitment to publish non-sensitive joint minutes to build public trust.
On the maritime side, Bangkok and Phnom Penh could revive technical talks on provisional arrangements of a practical nature, consistent with international law, to reduce friction while final delimitation remains pending. (The very existence of the 2001 MoU points to this logic.)
Educate before you legislate. If the government insists on public consultation, it should be deliberative, not plebiscitary. Commission independent primers on the MoUs; hold televised teach-ins with cartographers and international lawyers; publish side-by-side summaries of each article; invite Cambodian counterparts to explain their view of the process. The NIDA numbers tell us that many Thais want to learn more; leaders should meet citizens where they are rather than leverage confusion for a momentary mandate.
Lean on ASEAN’s tool kit. The ASEAN Charter provides for good offices, mediation and conciliation, and the TAC’s High Council exists on paper to help defuse disputes. These mechanisms are underused, in part because member states reflexively insist problems are “bilateral”. After this summer’s violence, quietly inviting a respected ASEAN elder or a mini-lateral working group to support confidence-building would align with regional norms while preserving bilateral ownership.
Be candid about trade-offs. There is no “win” that delivers immediate sovereignty gains without costs. The choices are between managed uncertainty under joint rules and unmanaged uncertainty without them. Investors, border communities and navies all prefer the former.
Therefore, a referendum to blow up the only ladders available for climbing out of a century-old problem is not strategy; it is theatre.
The 2000 and 2001 MoUs are imperfect tools that can be improved. They are also the architecture within which Thailand and Cambodia have, painstakingly, moved from confrontation to coordination; however, haltingly since 2000. Pulling that architecture down will not reveal a finished house; it will expose both neighbours to the weather.
Anutin’s government says it wants to demonstrate resolve. The harder, braver choice is to demonstrate responsibility. Hold the line against politicising maps, invest in expert-led demarcation and show the Thai public that durable sovereignty is built through procedures, not plebiscites.
The costs of getting this wrong are not abstract. They are counted in human displacement, damaged livelihoods and the corrosion of ASEAN’s still-fragile security consensus. If Bangkok chooses symbolism over substance, it will win the day’s headlines and lose tomorrow’s stability.
Seng Vanly is a Phnom Penh-based Geopolitical Analyst. The views and opinions expressed are his own.
