Thai soldiers and members of the media visit an area close to the border with Cambodia near Sadok Kok Thom Historical Park in Thailand’s Sa Kaeo province on February 5, 2026 | AFP
In a report by the International Crisis Group, the authors assert that to avoid more war, the Thailand and Cambodia should restore normal diplomatic ties and resume work on demarcating their shared border.
What’s new? Fighting between Cambodia and Thailand over a border dispute killed at least 150 people and displaced almost a million more in 2025. Now, the ceasefire between the two countries is fraying, while diplomacy has stalled.
Why does it matter? The 2025 combat was the costliest yet between the two countries and the worst confrontation ever between two members of the Association of South East Asian Nations. War could break out again if Bangkok and Phnom Penh do not improve relations.
What should be done? Leaders in Bangkok and Phnom Penh should work to normalise diplomatic ties, reconvene the Joint Boundary Commission in order to resume the surveys that will let the sides demarcate the land border, when circumstances allow, and cooperate on a program of demining affected areas.
Executive Summary
After two rounds of fighting in 2025 over a longstanding territorial dispute along their 800km land border, a ceasefire between Cambodia and Thailand is under strain, threatened by heightened nationalism on both sides and mutual allegations of violations. Tensions between the two countries resurfaced early in 2025, erupting into combat that dwarfed earlier clashes in scale. When the shooting stopped on 27 December, Thailand had the upper hand, holding most of the contested areas as well as slivers of Cambodian territory. In May, Bangkok withdrew from a 2001 bilateral agreement on how to resolve overlapping maritime claims, leading Phnom Penh to initiate compulsory conciliation – a non-binding international legal proceeding – under the UN Convention on the Law of the Sea. In turn, Thailand suspended participation in bilateral mechanisms on land border demarcation, leaving negotiations in limbo. To avoid more war, the two countries should put nationalist fervour to the side and overcome their mistrust, starting with restoring normal diplomatic ties and resuming efforts to jointly demarcate the land border.
