Renewed Tensions on the Cambodia-Thailand Border: History, Consequences, and the Path to Resolution

Introduction

Tensions flared once again between Cambodia and Thailand following a brief but deadly border clash on May 28, 2025, in the disputed area of Chong Bok. The skirmish resulted in the death of a Cambodian soldier and reignited long-standing disputes over territory along the border. Although both governments quickly reached a local ceasefire through field commanders, the incident highlights the fragility of peace in a region shaped by colonial-era boundaries and unresolved nationalism. As both sides mobilize troops and diplomatic rhetoric sharpens, the urgency for a long-term solution becomes ever more apparent.

Source: Reuters

Latest Developments: Timeline of the Skirmish

• May 28, 2025: Armed forces from both Cambodia and Thailand clashed in Chong Bok, a lightly populated forested border region claimed by both nations. The firefight, which lasted around 10 minutes, left one Cambodian soldier dead. Each country accused the other of initiating the violence.
• May 29: Senior military commanders on both sides communicated via a joint hotline, leading to a prompt ceasefire and temporary de-escalation. However, mutual distrust remains high.
• Early June: Thailand began reinforcing its military presence along vulnerable border zones, while Cambodian officials accused Thai forces of encroachment and aggressive patrolling.
• June 14 (scheduled): A session of the Joint Border Commission (JBC) is planned, where both governments are expected to present claims and negotiate terms for conflict prevention and demarcation.
• Meanwhile, Cambodia has announced plans to bring the issue to the International Court of Justice (ICJ), though Thailand has reiterated it does not recognize the court’s jurisdiction in this context.

Historical and Political Roots of the Conflict

The Cambodia-Thailand border conflict is deeply rooted in colonial-era treaties and divergent interpretations of international law.

• Colonial Border Ambiguity: The 1907 Franco-Siam Treaty, signed between French Indochina and Siam (now Thailand), created borders that were vague in certain regions, particularly near culturally significant sites like Preah Vihear Temple.
• ICJ Rulings and Rejections: In 1962, the ICJ awarded Preah Vihear to Cambodia, and in 2013, it clarified that the surrounding area also belonged to Cambodia. Despite this, Thailand has consistently challenged these rulings, arguing that adjacent territories were never clearly defined.
• Domestic Political Calculations: In both countries, the border dispute is frequently used as a tool for political mobilization. Cambodian leaders often invoke the issue to stir national pride, while Thai political actors face pressure from nationalist groups demanding a firm response.
• Uncoordinated Legal Approaches: While Cambodia advocates for international legal resolution, Thailand prefers bilateral negotiations and does not accept ICJ jurisdiction over the broader territorial claims.

Impacts and Risks

The renewed conflict has triggered several immediate and potential consequences:

• Military Escalation: The deployment of reinforcements on both sides increases the likelihood of accidental encounters or further skirmishes.
• Economic Disruption: Border crossings, such as the Poipet checkpoint, have been closed or restricted, hampering trade and affecting thousands of borders residents dependent on cross-border commerce.
• Public Sentiment and Protests: Nationalist protests erupted outside the Cambodian embassy in Bangkok, with calls for stronger Thai military response. In Cambodia, social media has amplified outrage over the soldier’s death, fuelling anti-Thai sentiment.
• Regional Diplomatic Strain: The conflict places pressure on ASEAN’s credibility in conflict mediation, especially after Malaysia and China offered to facilitate talks, albeit with no concrete results so far.

Possible Solutions and Recommendations

To prevent further escalation and foster long-term peace, several diplomatic, legal, and practical steps should be considered:

1. Strengthen Bilateral Mechanisms (JBC)
   The Joint Border Commission should meet more frequently and establish clear protocols for patrol coordination, surveillance, and dispute reporting.
2. Local De-escalation Protocols
   Create hotlines and direct lines of communication between local military commanders. Ban unilateral construction, such as fencing or trenches, without prior notification.
3. ASEAN or Third-Party Mediation
   Given the limitations of bilateral talks, ASEAN should play a more active role. Neutral countries like Malaysia or observers such as China could assist as facilitators in talks that lead to binding, peaceful agreements.
4. Coordinated Legal Engagement
   If Cambodia proceeds with its ICJ filing, both parties should negotiate terms for mutual jurisdiction acceptance. Alternatively, a neutral arbitration panel could be formed, with both nations agreeing to abide by its decisions.
5. Cross-border Development Projects
   Initiating joint tourism and trade zones, particularly in disputed areas, could shift the focus from division to cooperation. Cultural exchange canters or eco-tourism sites near Preah Vihear, for example, could foster mutual economic benefit.
6. Transparent Communication with the Public
   Governments must clearly explain their diplomatic goals and avoid inflammatory rhetoric. Managing nationalism is essential to prevent domestic pressures from derailing peaceful negotiations.

Conclusion

The latest clash between Cambodia and Thailand serves as a stark reminder of the enduring volatility along their shared border. With deep historical roots and complex political undercurrents, the dispute requires more than a temporary ceasefire. Lasting peace will only be achieved through consistent dialogue, transparent legal processes, and shared economic interests. If leaders on both sides can commit to these principles—and if regional actors like ASEAN step up—the border may one day become a symbol of unity rather than division. Without this, however, the region risks being caught in a cycle of tension that undermines both national security and regional stability.