December 26, 2025
Dr. Rujira Bunnag
Naewna Online
Column of Rules, Regulation and Business
Publicized on Friday, December 19, 2025
The Kuala Lumpur Peace Accords, or the Kuala Lumpur Peace Declaration, executed on October 26, 2025, were formally signed by the Thai and Cambodian leadership, with President Donald Trump of the United States and Mr. Anwar Ibrahim, Prime Minister of Malaysia in his capacity as Chairman of ASEAN, acting as witnesses. The agreement was presented as a comprehensive framework intended to terminate the armed confrontation and protracted border disputes between Thailand and Cambodia, thereby projecting an image of peace-building leadership to the international community.
President Trump, in particular, emerged as a neutral person in the narrative of mediation, cultivating an international image as a peace leader representing a global superpower. This portrayal was subsequently reinforced during his address to the 80th Session of the United Nations General Assembly, wherein it was asserted that armed conflicts involving eight states worldwide—including the Thai–Cambodian conflict—had been resolved within a seven-month period during his tenure. Such declarations, in practical terms, also operated to consolidate domestic political legitimacy and electoral support within the United States.
Mutatis mutandis, the Prime Minister of Malaysia, Mr. Anwar Ibrahim, likewise accrued political capital and international recognition in his capacity as ASEAN Chair, presenting himself as a regional intermediary and architect of peace.
The Thai Prime Minister who affixed his signature to the agreement has remained confronted with the operational realities on the ground. Cambodian forces have continued to reinforce their military presence and to engage in deliberate acts of provocation, including the covert emplacement of landmines within Thai sovereign territory. These actions have resulted in repeated incidents of serious injury and permanent disability among Thai frontline personnel, daily. Such conduct constitutes a manifest breach of the Ottawa Convention, to which both Thailand and Cambodia are States Parties. Furthermore, the peace process appears to have been accompanied by an ancillary Thai–United States arrangement concerning cooperation in the trade of rare earth minerals—an arrangement whose substantive terms have not been disclosed to the Thai public and whose constitutional ratification by Parliament remains, at best, uncertain.
The catastrophic flooding in southern Thailand temporarily eclipsed public scrutiny of the border conflict. Be that as it may, once the humanitarian crisis subsided, Cambodian forces resumed their hostile conduct, deploying landmines and utilizing military weaponry accumulated during the ceasefire period contemplated under the Kuala Lumpur framework—reportedly with support from arms-producing states. These actions precipitated renewed armed engagements with Thai frontline units, resulting in additional casualties and fatalities, and thereby reigniting hostilities notwithstanding the ostensible existence of a peace agreement.
In contradistinction to the empirical realities, the leaders of the witnessing states issued public statements urging Thailand—unilaterally—to refrain from defensive and retaliatory measures, advancing justifications that bore little correspondence to the factual circumstances prevailing on the ground.
A particularly salient episode arose on December 13, 2025, when the Malaysian Prime Minister and President Trump publicly declared that Thailand and Cambodia had agreed to a cessation of hostilities effective at 22:00 hours on that date.
In point of fact, no such consensus had been reached by either party. Armed confrontations continued unabated, and further Thai military personnel were killed in action.
It bears emphasis that, whether in the realm of international relations or private commercial dealings, binding legal obligations arise exclusively from the concordant will of the parties concerned. Consent cannot be made by external actors, nor can even eminent witnesses prescribe the content or existence of obligations absent mutual assent. The aforementioned public pronouncements therefore stand in fundamental tension with the cardinal principle of consent underpinning both treaty law and contract law.
Subsequently, the Malaysian Prime Minister retreated from his earlier position, clarifying that his statements were intended merely as an expression of support for de-escalation and renewed dialogue, rather than an assertion of an existing ceasefire agreement.
It must further be observed that the declaration governing the Thai–Cambodian peace arrangement is conspicuously devoid of enforcement mechanisms or punitive measures capable of addressing non-compliance by either party—a lacuna that significantly undermines its normative and practical efficacy.
Cambodia has, in practice, failed to honour multiple undertakings, including obligations relating to ceasefire and de-escalation (notably, the cessation of landmine deployment within Thai territory), the withdrawal of heavy weaponry, the clearance of existing explosive remnants of war for the safety of both sides, and genuine cooperation in suppressing transnational criminal activity, including large-scale fraud operations and human trafficking.
Nevertheless, even in the absence of express enforcement provisions within the declaration itself, recourse may be had to the Vienna Convention on the Law of Treaties 1969 (VCLT). Pursuant to Article 60 thereof, a material breach by one party may entitle the other to invoke diplomatic countermeasures, engage in coercive diplomacy, or suspend performance of treaty obligations.
This holds particular significance where the breach implicates obligations of a humanitarian or human rights character. While Article 60, Vienna Convention on the Law of Treaties 1969 permits suspension or termination in cases of material breach, it also acknowledges the special status of obligations Erga Omnes, the violation of which constitutes an affront to the international community as a whole. Under the maxim inadimplenti non est adimplendum, a party in default cannot insist upon performance by the other. Injured states may accordingly adopt countermeasures—subject to established legal constraints—including border closures or actions designed to degrade the military capacity of the breaching state.
With respect to international responsibility, a state found to have violated its international obligations incurs liability under both criminal and civil regimes. Serious breaches of international humanitarian law—such as torture or war crimes—may give rise to proceedings before the International Criminal Court or other specialized tribunals, while claims for reparation may be pursued before international judicial bodies, including the International Court of Justice or the International Criminal Court where jurisdiction is established.
In the final analysis, the pattern of conduct exhibited in the Thai–Cambodian context reveals a persistent absence of genuine commitment on the part of Cambodia to a bona fide cessation of hostilities. On the other hand, leaders of some countries have sought to instrumentalize the conflict as a vehicle for personal or political aggrandizement—an enterprise constructed, regrettably, upon the loss of life and human suffering occasioned by the armed confrontation.
