The conflict between Cambodia and Thailand escalates again—no end in sight.

Key Chapter Title List

1. Collapse of the Trump-Brokered Ceasefire Agreement
2. Background of the October Kuala Lumpur Peace Accord
3. Ceasefire Negotiations and Fragile Consensus Following the July Conflict
4. Agreement Content and Interim Objectives
5. Resumption of Conflict in November and Breakdown of Trust
6. Thailand's Domestic Politics and Military Motivations
7. Cambodia's Strategic Considerations and Relations with the United States
8. Prospects for Escalation and Lack of Solutions
9. Author and Institutional Disclaimer

Document Introduction

This report is co-authored by Joshua Kurlantzick, Senior Fellow for Southeast Asia and South Asia at the Council on Foreign Relations, and research assistant Annabel Richter. It aims to provide an in-depth analysis of the evolution of the 2023 armed border conflict between Cambodia and Thailand, the reasons for the failure of short-term ceasefire agreements, and the underlying drivers of the ongoing escalation. The report focuses on the multiple ceasefire efforts, achieved through international mediation and rapidly broken, since the large-scale conflict erupted in July 2023. Using the October 26 signing of the Kuala Lumpur Peace Accord and its collapse in early November as a core case study, it reveals how domestic political calculations and strategic interests in both countries ultimately outweighed the pursuit of peace behind the facade of negotiations.

The report first reviews the conflict's background: long-standing tensions over the 500-mile disputed common border escalated into a five-day full-scale exchange of fire in July 2023, resulting in over 40 deaths, tens of thousands displaced, and stirring strong nationalist sentiment within Thailand, thereby strengthening the influence of the Thai military. Subsequently, with mediation from Chinese, Malaysian, and U.S. officials, both sides engaged in multiple rounds of ceasefire talks and agreed to "stop fighting" at a special meeting in Malaysia on July 28. However, this consensus showed cracks within hours due to mutual accusations.

During the ASEAN Summit held in Malaysia in October, Cambodian and Thai representatives signed the Kuala Lumpur Peace Accord, witnessed by then-U.S. President Donald Trump and Malaysian Prime Minister Anwar Ibrahim. The agreement was seen as the next logical step towards long-term de-escalation, containing a series of interim objectives including the release of prisoners of war, withdrawal of heavy weapons from disputed areas, establishment of new mine clearance procedures, and the creation of a politically neutral observation team. The signing was initially viewed as a positive signal for conflict mitigation.

However, the third part of the report details the rapid unraveling of this fragile peace. In early November, four Thai soldiers were injured in Surin province adjacent to Cambodia, leading Thailand to unilaterally suspend the ceasefire on November 10. Subsequently, clashes occurred on November 12, resulting in Cambodian civilian deaths. Thailand canceled the planned prisoner release and accused Cambodia of newly laying landmines along the border (which Cambodia denied). These events completely destroyed mutual trust, making the prospect of returning to a ceasefire extremely slim.

The core analytical section of the report delves into the deep-seated reasons for both sides' lack of willingness to end the conflict. For Thailand, ahead of the March 2024 parliamentary elections, the military has an interest in sustaining border tensions to stoke nationalism, aiming to boost support for pro-military parties and prevent the progressive People's Party from winning an absolute majority. A state of conflict grants the military greater domestic political weight. For Cambodia, domestic public opinion is largely angry about the ceasefire failure and blames Thailand, putting pressure on the government if it appears weak. Simultaneously, Phnom Penh is focused this year on improving relations with the United States and may hope that blaming Thailand for sabotaging the ceasefire (an agreement prominently touted by Trump) will draw the U.S. closer to Cambodia and away from Thailand, although Thailand's status as a U.S. treaty ally and larger trade partner poses a challenge to this strategy.

The report ultimately concludes that the current border situation is tense and dangerous, with no signs of change in the short term. Conflict is likely to escalate further. Considerations of domestic political interests on both sides have outweighed the willingness to resolve the dispute through diplomacy, and the effectiveness of external mediation appears limited without supporting internal political will. This analysis is strictly based on public events, official statements, and expert commentary, aiming to provide an objective assessment of the conflict dynamics for the policy community and academia, and does not represent the institutional position of the Council on Foreign Relations.