US-Brokered Peace Shattered as Thailand–Cambodia Clashes Ignite Fears for Regional Stability

BANGKOK: A fragile peace deal brokered by U.S. President Donald Trump and Malaysian Prime Minister Anwar Ibrahim has shattered, as Thailand and Cambodia engaged in heavy cross-border fighting on Monday, including the use of Thai airstrikes. The renewed conflict poses a significant threat to stability within the Association of Southeast Asian Nations (ASEAN) bloc.

The fighting, which erupted around the long-disputed 817-km border, prompted an immediate call for de-escalation from ASEAN Chair Anwar Ibrahim. He urged both sides to exercise maximum restraint, warning that the renewed clashes “risks unravelling the careful work that has gone into stabilising relations between the two neighbours.”

The current hostilities are the most serious since a five-day conflict in July, which killed 48 people and displaced hundreds of thousands. While a ceasefire was brokered rapidly, the peace deal, which was expanded and witnessed by President Trump in October, quickly frayed.

Thailand last month announced it was halting the truce’s implementation, citing a landmine blast that seriously injured one of its soldiers. Thailand has repeatedly accused Cambodia of planting new landmines along the disputed frontier, a charge Phnom Penh has vehemently denied.

The long-standing issue dates back over a century, tracing to the 1907 mapping of the border by France during its colonial rule of Cambodia.

As artillery and small arms fire were reported in border towns, mass evacuations began on both sides. In Thailand, over 35,000 civilians were sheltered, while more than 1,100 families fled their homes in Cambodia’s Oddar Meanchey Province.

Politically, the former Cambodian leader Hun Sen took a strong stance, labelling the Thai military as “aggressors” and instructing his forces to exercise restraint, despite the military casualties and three civilian injuries reported on the Cambodian side.

The use of air power by Thailand to hit Cambodian military targets—in response to the alleged mobilization of heavy weaponry—marks a significant escalation that few Southeast Asian countries have seen in recent decades, placing immediate pressure on regional diplomatic efforts to prevent a full-scale border war.