Cambodia Rejects Claims of New Border Markers, Cites Century-Old Demarcation With Thailand

PHNOM PENH, Cambodia (Dec. 1, 2025) — Cambodia has rejected claims it is installing new border markers along its frontier with Thailand, saying officials are instead locating and restoring markers placed more than a century ago under French colonial-era treaties.

It Sotha, permanent secretary of the Secretariat of Border Affairs, said the temporary markers now being surveyed are only to identify boundary lines so that permanent markers, originally set between 1919 and 1920, can be restored to their documented positions.

“The Cambodia-Thailand border is an international boundary inherited from the French colonial period and defined by the Franco-Siam Treaties of 1904–07, the 1907 Protocol and related documents,” he said. “We have found 74 markers from the 1919–1920 Indochina-Siam demarcation, though many were damaged over time by natural conditions and conflict.”

Cambodia and Thailand established a Joint Border Commission in 1997, signed a memorandum of understanding in 2000 and formed a Border Demarcation Working Group in 2003 to preserve and relocate the original French-era markers. The group has operated officially since 2006 and has confirmed several markers remain in their original positions.

Prime Minister Samdech Thipadei Hun Manet on Nov. 27 dismissed allegations by an exiled opposition politician as misleading and lacking legal or technical evidence. He said while he prefers not to engage in public disputes, it is sometimes necessary to counter false information that could mislead the public and be used for political gain.

Samdech Thipadei Hun Manet urged politicians and commentators without technical expertise to refrain from making claims about the border and said the government is prepared to arrange presentations on proper methods of map analysis and demarcation.