CHENNAI: A century-old border dispute flared up on July 16, 2025, as fierce artillery exchanges between Thai and Cambodian forces displaced over 130,000 civilians and claimed at least 32 lives. The clash near the disputed Dangrek Mountains escalated into one of the region’s worst cross-border conflicts in years, reviving historical tensions and straining diplomatic ties. Although a ceasefire now holds, the fragile calm masks unresolved issues rooted in colonial-era borders, ancient temples, and nationalist rhetoric.
Historical roots
The Thailand-Cambodia border dispute traces back to a 1907 map drawn during French colonial rule over Cambodia. This map, central to Cambodia’s claims, delineated the 817-kilometre border but left ambiguities. Thailand, then Siam, contested parts of the demarcation, particularly areas with ancient Khmer temples.
Prasat Preah Vihear, an 11th-century temple on the Dangrek escarpment, remains the epicentre of this dispute. In 1962, the International Court of Justice (ICJ) awarded the temple to Cambodia but did not resolve ownership of the adjacent 4.6 square kilometres. Thailand has since rejected ICJ jurisdiction over the surrounding area. Intermittent skirmishes have persisted. Another flashpoint is Prasat Ta Muen Thom, a 12th-century temple in Thailand’s Surin province. Though within Thai territory, its proximity to the border and historical ties to the Khmer Empire fuel competing sovereignty claims.
Shared cultural heritage has not bridged the divide. In Surin, many Thai citizens speak Khmer, reflecting centuries of cultural interweaving. Yet, this shared identity often becomes a battleground for nationalist agendas, with leaders on both sides leveraging the temples to assert territorial and historical rights.
Temples and tensions
The disputes transcend land, rooted in national pride. The temples are not just relics but symbols of sovereignty. In 2008, Cambodia’s successful bid to designate Preah Vihear a UNESCO World Heritage Site sparked nationalist outrage in Thailand, leading to clashes from 2008 to 2011 that killed 40 people.
Tensions resurfaced in 2025. In May, a Cambodian soldier died in a border skirmish. By July, the situation escalated when five Thai soldiers were injured by landmines, which Bangkok alleged were recently laid by Cambodian forces—a claim Phnom Penh denied. Thailand responded by sealing border crossings, recalling its ambassador, and expelling Cambodia’s envoy. Cambodia downgraded its diplomatic presence in retaliation.
On July 24, 2025, fighting erupted near Prasat Ta Muen Thom. Thailand accused Cambodia of deploying surveillance drones and firing first, while Cambodia claimed Thai troops violated prior agreements by encroaching on the site. Thailand deployed F-16 fighter jets, and Cambodia countered with artillery and long-range rockets, including BM-21 and Type-90B PHL-81 systems. The human toll was severe: 14 Thai civilians, including a young boy, were killed, and over 130,000 Thai residents and 1,500 Cambodian families were displaced. Both sides alleged civilian targeting. Cambodia accused Thailand of using banned cluster munitions, a claim yet to be verified.
Personal politics
The conflict intertwines with political dynasties. Thai Prime Minister Paetongtarn Shinawatra, daughter of former PM Thaksin Shinawatra, faces off against Cambodia’s former leader Hun Sen and his son, Prime Minister Hun Manet. Once allies, their relationship has soured. In 2009, while in exile, Thaksin served as an adviser to Hun Sen. In June 2025, Hun Sen leaked a private call with Paetongtarn, in which she referred to him as “uncle” and mocked the Thai military. The fallout saw Thailand’s Constitutional Court suspend her on July 1, sparking protests and a leadership crisis in Bangkok.
In Phnom Penh, Hun Sen appears to be using the conflict to bolster his son’s authority amid Cambodia’s faltering post-pandemic recovery and Western economic pressure. In Thailand, the ruling Pheu Thai coalition grapples with economic stagnation and unrest, making concessions politically risky.
Diplomacy on edge
The clashes prompted swift international responses. ASEAN, chaired by Malaysia’s Prime Minister Anwar Ibrahim, urged calm and offered mediation, but Thailand insisted on bilateral talks. The United States, a Thai treaty ally, called for an immediate end to hostilities. China, a major economic partner of both nations, advocated dialogue but avoided mediation. The UN Security Council held an emergency session on July 25, where both sides reiterated accusations but expressed willingness to de-escalate.
China’s potential mediation role is complex. As Thailand’s largest trading partner and a key investor in Cambodia’s infrastructure and military, its impartiality is questionable. ASEAN members, particularly Vietnam with its own historical tensions, fear regional spillover. Travel advisories have been issued by Australia, Singapore, the US, Hong Kong, and mainland China, urging citizens to avoid border areas.
Trade frozen, lives disrupted
The economic impact has been severe. Cross-border trade, vital for both nations, has halted. Thailand closed all border checkpoints, and Cambodia imposed bans on certain Thai goods. Farmers and traders face mounting losses with no resolution in sight. Civilians have suffered most. In Thailand’s Sisaket province, rockets struck a petrol station, killing two students. Families like Phaiboon Yerngram fled with minimal possessions. In Cambodia’s Oddar Meanchey province, nearly 1,500 families remain in temporary shelters, uncertain of their future.
Cambodia’s unverified claim of Thai cluster munition use has raised global concern. If substantiated, it could invite legal scrutiny and complicate diplomatic efforts.
The road ahead
Despite the July 27 ceasefire, both sides maintain troops near the frontline. Trust remains scarce, and political will for lasting peace is elusive. The ICJ’s limited jurisdiction, given Thailand’s stance, restricts legal recourse. ASEAN’s consensus-based approach may struggle to yield results. With domestic pressures rising, both Bangkok and Phnom Penh risk stoking nationalist sentiments over seeking peace. The cost in lives, livelihoods, and regional stability is mounting. If diplomacy fails, the ceasefire may merely delay the next escalation.
Flashpoints on the border
Prasat Preah Vihear: Cambodian-controlled, culturally contested
Prasat Ta Muen Thom: In Thailand’s Surin province, claimed by both
Dangrek Mountains: Hosts multiple disputed sites
Weapons used in clashes
Thailand: F-16 jets, artillery
Cambodia: BM-21, Type-90B rocket systems
Controversy: Cambodia’s unverified
claim of Thai cluster munition use
What next
Best-case: Sustained ceasefire, ASEAN-led talks
Worst-case: Renewed conflict, regional destabilisation
X-factor: China’s role, protests in Bangkok
Over the years
1907: French map demarcates border, sowing seeds of dispute
1962: ICJ awards Preah Vihear to Cambodia
2008: Preah Vihear named UNESCO site; protests erupt
2008–2011: Clashes kill 40
2009: Thaksin appointed Cambodian adviser, sparking Thai outrage
May 2025: Cambodian soldier killed; tensions rise
July 1, 2025: Thai PM Paetongtarn suspended after leaked call
July 24, 2025: Fighting erupts near Prasat Ta Muen Thom
July 25, 2025: UN Security Council meets
July 27, 2025: Ceasefire declared
Sacred stone
Perched on the Dangrek Mountains, Preah Vihear, an 11-12th century Hindu temple, is a source of pride and contention for Thailand and Cambodia. In 1904, Thailand and French-ruled Cambodia agreed to a watershed-based border, but a 1907 French map placed the temple in Cambodia. Thailand accepted this until the 1950s, when disputes resurfaced. The ICJ’s 1962 ruling awarded the temple to Cambodia, leaving the surrounding land contested. A 2013 ICJ decision clarified Cambodia’s sovereignty over the immediate area. Tensions flared in 2008 after Preah Vihear’s UNESCO World Heritage designation, sparking clashes. Today, Cambodia controls the temple, but the adjacent area remains militarised. A lasting solution may require talks, with proposals like joint patrolling
