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

Key Chapter Title List

1. The Breakdown 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 Collapse 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 Resolution
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 Annabelle 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 dynamics driving the continued escalation of the conflict. The report focuses on the multiple ceasefire efforts, brokered by international mediation since the outbreak of large-scale conflict in July 2023, which were rapidly broken. 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, despite the appearance of negotiations.

The report first reviews the background of the conflict: the long-standing tensions between the two countries over a 500-mile disputed border area 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, multiple rounds of ceasefire negotiations were held. On July 28, during a special meeting in Malaysia, both sides agreed to halt fighting, but this consensus showed cracks within hours due to mutual accusations.

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

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, an exchange of fire occurred on November 12, resulting in Cambodian civilian casualties. Thailand canceled the planned prisoner release and accused Cambodia of laying new mines along the border (a claim 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, the military, ahead of the March 2024 parliamentary elections, has an interest in sustaining border tensions to incite 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, there is widespread public anger over the ceasefire failure, with blame directed at Thailand. The government would face domestic pressure if perceived as weak. Simultaneously, Phnom Penh has been working this year to improve relations with the United States. It may hope that blaming Thailand for sabotaging the ceasefire (an agreement highly publicized by Trump) could push the U.S. closer to Cambodia and further 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. The conflict is likely to escalate further. Domestic political interests in both countries have outweighed the willingness to resolve the dispute through diplomacy. 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. It aims 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.