How a Trump-Brokered Thailand–Cambodia Ceasefire Unravelled in Just Six Weeks

Six weeks after Thailand and Cambodia signed a high-profile ceasefire in Kuala Lumpur—witnessed by former US President Donald Trump and touted as a breakthrough for regional peace—the border is once again engulfed in violence. Fresh airstrikes launched by Thailand on Monday have not only shattered the fragile truce but have revived longstanding anxieties over a dispute that has simmered for more than a century.

How the Border Erupted Again After a Brief Calm

Before dawn on Monday, Thailand carried out airstrikes on Cambodian military positions. Bangkok said the action was retaliatory, claiming a Thai soldier had been killed and several wounded in an earlier Cambodian attack. Military authorities confirmed the destruction of a cable car and concrete steps leading to the Prasant Ta Krabei temple complex on the Cambodian side.

Cambodia denied initiating any attack. Its defence ministry accused Thailand of launching unprovoked strikes using tanks, toxic gas and artillery fire, hitting both military posts and civilian areas in Oddar Meanchey. Local officials reported three civilians injured. The diverging accounts signal a familiar pattern: each side blames the other for the trigger, while people living along the border flee in fear of another escalation.

By midday, thousands were evacuating their homes—many recalling how the fighting in July escalated within hours into aerial and rocket attacks.

Why the October Ceasefire Failed So Quickly

The October 26 agreement was ambitious in optics but limited in design. Brokered by Malaysia and witnessed by Trump, the deal sought to halt months of tension after July’s five-day conflict killed 43 people and displaced more than 300,000. But it lacked clear monitoring mechanisms, leaving enforcement entirely to the goodwill of two militaries that have long distrusted each other.

Cracks appeared almost immediately. On November 11, Thailand suspended the implementation of the pact after a landmine blast injured a soldier. Cambodia rejected accusations of planting new mines. A day later, renewed exchanges of fire left at least one person dead. With neither side willing to concede ground—literally or politically—the ceasefire unraveled at speed.

The Deep Historical Faultlines Behind the Dispute

The Thailand–Cambodia frontier has never been fully demarcated, and its most contentious stretches derive from a 1907 French colonial map. Thailand disputes sections around the 11th-century Preah Vihear temple, which sits atop a strategic cliff. While the International Court of Justice ruled in 2013 that the temple promontory belongs to Cambodia, surrounding ridges and slopes remain contested.

Tensions spiked in 2008 when Cambodia successfully secured UNESCO World Heritage status for the temple. Military deployments on both sides followed, leading to artillery exchanges in 2011. For both countries, even minor territorial concessions carry deep symbolic weight—linked to historical grievances and national identity.

Why This Border Is Prone to Sudden Flare-Ups

• Multiple factors make the region exceptionally volatile:
• Unclear borders that allow for conflicting patrols and parallel claims.
• Heavily militarised forward posts , where skirmishes can escalate within minutes.
• Political incentives for leaders to appear uncompromising on issues of sovereignty.
• Civilians living close to conflict lines , increasing pressure on governments when casualties occur.
• No neutral monitoring mechanism , unlike other long-running ceasefire zones in Asia.

This week’s breakdown followed the familiar sequence: troop movements, accusations of encroachment, conflicting casualty reports, and rapid military retaliation.

Implications for Regional Diplomacy and Trump’s Peacemaking Image

The collapse of a ceasefire witnessed by Trump and brokered by Malaysia has diplomatic consequences. For Trump, who framed the October signing as evidence of his deal-making prowess, the renewed violence undercuts that narrative. For ASEAN, it highlights the limits of regional mediation when border disputes are tied to national pride and historical grievance.

Malaysia’s Prime Minister Anwar Ibrahim has urged restraint, calling on both nations to activate communication channels. But ASEAN lacks an enforcement mechanism, and without an impartial observer on the ground, misperceptions and mistrust are likely to persist.

What the Region Should Expect Next

Over the coming weeks, several factors will determine whether the crisis worsens or stabilises:

• Military movements : Any reinforcement by either side could fuel further clashes.
• Political messaging : Cambodia’s former PM Hun Sen calling for restraint may help prevent immediate escalation.
• Humanitarian pressure : Growing displacement could trigger international involvement.
• Legal arguments : Both sides may revive the ICJ ruling to justify their positions.
• ASEAN intervention : A push for a monitoring mission or new talks is likely but will require political will from both capitals.

For now, the Trump-backed truce is effectively defunct. What was presented as a diplomatic milestone in late October has succumbed to the unresolved history, strategic anxieties and fragile trust that have repeatedly undermined peace along the Thailand–Cambodia border.