An ASEAN-led observer team visited a contested boundary marker on the Cambodia-Thailand frontier on August 4, arriving at 9:21 a.m. local time to inspect conditions on the ground, Cambodia's defense ministry said. The visit came roughly two weeks after Thailand's military announced it had finished the first section of a permanent border fence, underscoring how both sides are still managing a dispute that has produced two ceasefires in the past year.
The ASEAN Observer Team in Cambodia, known as AOT-KH, traveled to Boundary Pillar No. 37 — locally called the "Unity Marker" — in Kdeb Thmar village, Kouk Romeat commune, Thmar Puok district, in Banteay Meanchey province. The mission was led by a head of mission from the Philippines and coordinated with the Cambodian Liaison Group, according to Cambodia's defense ministry, which said the visit was meant to give observers direct knowledge of the site so they could verify and report on conditions along the border. The ministry added that Cambodia remains committed to resolving outstanding border issues through the Thailand-Cambodia Joint Boundary Commission and existing bilateral agreements.
Thailand presses ahead with a permanent fence
On July 22, Thailand's military said it had completed a 1.3-kilometer stretch of reinforced concrete panels, topped with steel mesh and concertina wire, in the eastern Pong Nam Ron district. Chief of Defence Forces General Ukrit Boontanon described the section as "stable, strong and durable" during a media tour of the site, and said the panels had been test-fired and confirmed able to resist small-arms fire.
Ukrit said the military intends to add more than 7 kilometers of connected fencing, assessing other stretches of the 817-kilometer frontier where terrain allows similar construction. Not every part of the border will get the same treatment, he indicated. "Each area has different conditions," he said. "We will build where it is beneficial and where it can be done without creating future problems."
The fence project follows directly from the two rounds of fighting in 2025, and Thai officials have framed it as a long-term security investment rather than a temporary measure tied to the current ceasefire. Troops remain deployed on both sides of the frontier, a posture that has not changed materially since the December 2025 agreement froze troop positions.
Two ceasefires in twelve months
The current monitoring arrangement traces back to fighting that broke out in May 2025 over a dispute rooted in the position of ancient temples and colonial-era border demarcation. That escalated in July 2025 into five days of cross-border fighting involving air strikes and artillery, and combined with a second round of clashes later in the year, the fighting killed nearly 150 people and displaced roughly 300,000.
Cambodia and Thailand signed their first ceasefire on August 7, 2025, at an extraordinary General Border Committee meeting in Kuala Lumpur, with the United States, China and Malaysia taking part as third-party observers and both governments pledging not to increase troop numbers along the border. The U.S. State Department welcomed the meeting at the time as a step toward setting up an ASEAN observation mechanism. That truce did not hold: it broke down in late 2025 after a Thai soldier was injured by a landmine, an incident Thailand blamed on Cambodia. Thailand suspended parts of the agreement and expanded airstrikes, and the renewed clashes displaced more than 500,000 people combined and killed at least 100 before a second ceasefire was signed on December 27, 2025. Under that agreement, both sides committed to freezing troop positions and keeping their defense chiefs in direct contact.
Displacement disputes still unresolved
Cambodian officials say the practical effects of the fighting have not gone away. The defense ministry has said roughly 1,870 displaced families — about 8,790 people, including 1,980 children — remain unable to return home near the Chey Chomneas border checkpoint, alleging that Thai forces continue to occupy the area with barbed wire and shipping containers and that homes there have been destroyed. Cambodia separately alleges that Thai forces still control the O'Phlouk Damrei area, which it describes as illegally occupied territory.
Thailand has not issued a matching public account of conditions at either site. The two governments' figures and characterizations of specific locations along the border have diverged at multiple points over the past year, including during the earlier landmine dispute that broke the first ceasefire.
A separate track for the maritime boundary
Beyond the land border, Cambodia and Thailand are pursuing their overlapping maritime boundary claim through international arbitration — a route Thailand had previously avoided in favor of bilateral negotiation. Until recently, Bangkok had argued that direct talks between the two governments favored its position more than an international panel would, and the shift toward arbitration marks a change from that earlier stance. That process runs on its own timeline, separate from the Joint Boundary Commission work Cambodia's defense ministry pointed to after the August 4 marker inspection.
The Boundary Pillar No. 37 visit falls just short of the one-year mark since the original ceasefire mechanism was set up in Kuala Lumpur. ASEAN's observer role has continued through both ceasefires and the gap between them, even as the two governments' accounts of what is happening on specific stretches of the border keep pulling apart.