From Thmar Da to Surin: A Cambodia-Thailand Border Under Control but Without Solution

Along the Cambodia-Thailand border, the post-2025 Cold War is evident in the taut barbed wire, aligned metal containers, and militarized posts that now dot the border communes of Pursat and Oddar Meanchey.

Boeung Trakuon border post in Banteay Meanchey province @AKP

Although direct combat has ceased since the December 27, 2025 ceasefire, the Cambodian and Thai armies remain in defensive positions, frozen on either side of a border line that has become a space of tension managed by diplomacy.

A Militarized but Controlled Border Line

Since the truce signed at Prum-Pak Kard, the authorities in Phnom Penh and Bangkok have maintained a significant military presence along the border, with reinforced forward posts in the Cambodian provinces of Pursat, Oddar Meanchey, Preah Vihear, and Banteay Meanchey, and in the Thai provinces of Surin, Sisaket, and Ubon Ratchathani. Thai authorities have also directly taken control of several crossing points, extending the increased militarization of the border area.

In Thmar Da, Veal Veng commune in Pursat province, the situation exemplifies this constrained coexistence: Bangkok's forces have installed barbed wire and containers, with three new elements added on March 26, 2026, effectively blocking National Road 55 and preventing dozens of displaced families from returning home. The 76 families gathered at Hun Sen Promaoy School alone embody the human reality of a border turned military front, where civilian life remains suspended between the lines.

A Diplomacy of Restraint and Firmness

It is in this context that Vice-Prime Minister and Foreign Minister Prak Sokhonn led a diplomatic visit to Thmar Da on March 27, bringing together the diplomatic corps and representatives of international organizations. The objective: to witness on-site the situation of the displaced populations and reaffirm Cambodia's main guiding principle: the rejection of any border modification by force and the absolute priority given to the peaceful resolution of disputes, in accordance with international law and bilateral agreements.

At the same time, Bangkok and Phnom Penh continue a dialogue conducted under regional mechanisms, notably the Regional Border Committee (RBC) secretariat and, indirectly, ASEAN diplomacy. The two parties have reiterated, in recent meetings, their commitment to respecting the ceasefire, avoiding any provocative maneuvers, and initiating a progressive demilitarization of contested areas. Yet, the situation on the ground remains a tense demarcation line, where diplomacy advances more slowly than military posts and barbed wire.

A Province in Limbo, a Strategically Frozen Border

The provinces of Pursat and Oddar Meanchey, alternating between deserted villages and control posts, embody this frozen border: friction zones where Phnom Penh accuses Bangkok of illegally occupying 14 zones, while Bangkok rejects or downplays these charges. French authorities, like those of several Western partners, continue to advise against travel within 30 to 50 kilometers of this line, highlighting a security situation still deemed uncertain.

Behind this configuration, Cambodia seeks to project an image of conciliatory firmness: resolute defense of its sovereignty, but refusal of war, investment in diplomacy, participation in regional mechanisms, and repeated reaffirmation of the no-use-of-force rule. While the border with Vietnam is the subject of growing integration and institutional cooperation, the Cambodian-Thai zone remains, de facto, a diplomatic front as much as a military one, where every barbed wire, every closed crossing point, and every unit movement bears witness, in reverse, to the scale of the peace challenge.