Cambodia & Thailand: A border that should unite, not divide

By Arnaud Darc

On 27 September 2025, in Chong An Ma, on a ridge where daily life has all too often become a dead end of barbed wire, closed roads and tense faces, the inevitable happened. A brief, brutal flash: weapons were heard.

According to Thai sources, the first shots were fired by Cambodian forces. Phnom Penh replied that it was Thai mortar fire that hit An Ses. Less than an hour later, silence had returned. No ground movement, no victory, but a silent defeat nonetheless: that of the families, Cambodian and Thai, who are paying the price of fear, interrupted income and a suspended daily routine.

Neither the Khmer nor the Thai people should ever have to pay this price.

The law as an anchor

For beyond emotions and national narratives, one thing remains certain: international law lights the way. In 1962, the International Court of Justice ruled that the Temple of Preah Vihear belongs to Cambodia and demanded the withdrawal of Thai troops. In 2011, reiterating the urgency of the situation, the Court again called for the simultaneous withdrawal of the two armies and the presence of ASEAN observers to avoid a spiral of armed confrontation.

Thailand has complied in practice, although it has never explicitly recognised the legitimacy of this request. Cambodia, for its part, brandishes these decisions not out of provocation but out of loyalty to a simple rule: it is law and not force that guarantees the security and dignity of neighbouring nations.

The border framework

This is also why the Memorandum of Understanding signed in 2000 and registered with the United Nations remains crucial. The two governments committed themselves to preserving the status quo until the joint demarcation process was completed. A precise and rigorous process, entrusted to the Joint Boundary Commission: restoring the old pillars, drawing up joint maps, undertaking surveys, inspecting the terrain and finally installing new markers.

And yet, storms are still brewing. The controversy surrounding the border pillar 42 illustrates the inability of technicians to resolve issues of sovereignty on their own. On the ground, the reality is stark and paradoxical: some Thai farmers cultivate plots of land on Cambodian territory, while Khmer families live and work as close as possible to the disputed line. As Prime Minister Hun Manet recently reminded us, these tensions must remain within the JBC, and not be rekindled by unilateral maps or makeshift fences.

The human cost

The border is not an abstract feature, it's a place where people live. One fence here, and an entire market is extinguished. By 2024, trade between Thailand and Cambodia had exceeded 9.5 billion US dollars. The Poipet-Aranyaprathet crossing alone accounts for almost $2 million worth of goods a day.

Behind these figures, there are voices. A vendor in Sisophon confides: "When the border closes, I have to throw away my fruit. I can no longer pay my children's school fees". In Sa Kaeo, a Thai lorry driver lamented: "If the barrier stays closed for two days, I've already lost my week. And yet my bank instalments don't wait for me. These painful stories are written with each incident, and they are tragically similar.

A shared history

It would be forgetting too quickly that these peoples, long before colonial borders and coordinates on paper, coexisted fluidly across this escarpment. Buddhism, royal blood, lively exchanges at seasonal markets: everything linked Khmer and Siamese. The Temple of Preah Vihear itself, the grandiose work of the Khmer sovereigns, became a place of meditation for generations of monks from Thailand. There is nothing in our long history to suggest hostility. We are neighbours, linked to the past and committed to the future.

A pragmatic way forward

If we want different results, we have to change the scenario. Here is a realistic proposal, a 90-day pilot plan to turn the page on the incidents:

1. Withdraw troops from the immediate area, as required by the ICJ.

2. Deploy a small contingent of ASEAN civilian observers to record each episode and publish a daily bilingual report.

3. Protect the movement of goods within ‘corridors of economic continuity’, controlled by ASEAN.

4. Adopt ‘friction rules’: ban on lethal weapons within a 5km radius, strictly non-lethal use for crowd control, obligation to report incidents via a common hotline.

5. Weekly meetings in border towns with public reporting.

Success would be measured simply: zero armed confrontations, a return to 90% of normal trade flows, and the holding of a joint public event, bringing together Thai and Cambodian communities.

This is not a dream, but continuity. On 10 September 2025, at a special meeting of the General Border Committee, the two governments had already agreed to back off the heavy artillery, approve the presence of regional observers, reopen crossings for trade and counter misinformation campaigns.

Political realities and room for manoeuvre

But no one is unaware of the inertia of nationalism. In Bangkok, the generals and an ardent public demand firmness. In Phnom Penh, no leader can exercise restraint without being suspected of weakness.

So it's not a question of concessions, but of ‘experimentation’, of a controlled pause. Leaders will be able to say to their citizens:

‘We are not capitulating, we are testing a truce to preserve lives and livelihoods.’

And if this march is judged to be too ambitious, there is a fallback lever: unofficial dialogue, known as ‘Track II’. Researchers, clerics, former military officers, entrepreneurs: these voices can prepare the ground, prepare the solutions, so that when the decision-makers take the plunge, the options are already familiar, born of their own civil societies.

The first step

But even before agreements and communiqués, peace can take a humble, immediate form. Tomorrow morning, 8 o'clock, Chong An Ma and An Ses: two commanders pick up the phone and exchange a brief greeting: "Good morning. All's quiet here.

This simple gesture is already part of the interim observer scheme approved by the GBC. It costs nothing, but it instils a reflex for peace.

A decisive choice

This plan protects Cambodian sovereignty, offers Thailand the opportunity to show regional leadership and, above all, restores dignity to the citizens forced to pay the price for a conflict that is not theirs.

The choice is there: the border can remain a battlefield, or once again become a bridge.

Let this be the last week in which our border freezes in the silence of annihilated trade and the din of weapons. The hand is now extended to the leaders. Cambodia will remain faithful to the law. Thailand, as a larger power, can turn a tense week into a historic turning point.

It is up to us, the neighbouring peoples, to say: the border must no longer divide, it must unite.