Explainer: How did Thailand and Cambodia reach a ceasefire?
After five days of deadly clashes, Thailand and Cambodia agreed to an “immediate and unconditional” ceasefire. Asia in Focus takes a look at how the conflict and ceasefire unfolded.
July 28, 2025: Cambodian PM Hun Manet and Thai Acting PM Phumtham Wechayachai agree to ceasefire during Malaysia peace talks chaired by ASEAN Chair PM Anwar
Tensions along the disputed border between Thailand and Cambodia erupted into a full-scale military confrontation on Thursday, July 24, marking the most severe escalation in over a decade.
Soldiers from both nations exchanged heavy gunfire near the ancient Prasat Ta Muen Thom and Ta Moan temples, leading to civilian casualties, mass evacuations, and a complete collapse of diplomatic relations.
Timeline of the conflict:
May 2025: A Cambodian soldier is killed in a skirmish over contested territory, reigniting simmering tensions.
July 21-23, 2025: A landmine blast injures five Thai soldiers in Ubon Ratchathani province, prompting Thailand to accuse Cambodia of breaching the Ottawa Treaty on anti-personnel mines. Cambodia denies the claim, stating the blast occurred on its side due to leftover unexploded ordnance.
Wednesday, July 23, 2025: Thailand recalls its ambassador to Cambodia and announces the expulsion of Cambodia's envoy in Bangkok.
Thursday, July 24, 2025:
In a reciprocal move, Cambodia also withdraws its diplomatic staff from Bangkok and orders Thai diplomats to leave Phnom Penh. Cambodia officially downgrades diplomatic relations with Thailand to their "lowest level."
Clashes erupt near the Ta Muen Thom and Ta Moan temples. Both sides accuse the other of firing first.
Thai army reports at least 12 Thai civilians killed and multiple injured from Cambodian artillery fire, including an eight-year-old boy. Most casualties reportedly occurred in Si Sa Ket province, where six people were killed after shots were fired at a gas station.
Thailand deploys F-16 fighter jets, with one reportedly bombing a Cambodian military target. Cambodia's Ministry of National Defence condemns this as "brutal and illegal military aggression," claiming Thai jets dropped bombs on Cambodian territory.
Thailand closes all border checkpoints with Cambodia and urges Thai nationals to evacuate Cambodia.
Cambodia's Prime Minister Hun Manet states Cambodia has "no choice but to respond with armed force against armed aggression."
Reports emerge of a Thai hospital (Phanom Dong Rak Hospital in Surin province) allegedly targeted by Cambodian artillery.
Approximately 40,000 Thai civilians from 86 villages near the border are evacuated.
Sunday, July 27, 2025: At least 38 people are reported killed and at least 300,000 displaced since Thursday, according to Thai and Cambodian officials.
Roots of the conflict
While the confrontation may appear sudden to outside observers, it has long-standing roots in territorial disputes along the 800-kilometre Thai-Cambodia border.
The Thai-Cambodian border dispute has persisted for over six decades, spanning roughly 800 kilometres of contested and ambiguously demarcated territory
The 1,000-year-old Preah Vihear temple, awarded to Cambodia by the International Court of Justice (ICJ) in 1962, remains a persistent flashpoint. While Thailand acknowledges the 1962 ruling on the temple’s sovereignty, the precise demarcation of the surrounding border area remains unresolved and highly volatile.
In 2013, the ICJ clarified its earlier judgment, affirming Cambodia’s sovereignty over the entire promontory of Preah Vihear and ordering Thailand to withdraw all military forces from the area.
However, Thailand does not accept the general compulsory jurisdiction of the ICJ and has not done so since 1960. This means any legal dispute involving Thailand at the ICJ requires its specific consent, on a case-by-case basis.
This legal stance has resurfaced as Cambodia recently submitted a new request to the ICJ concerning other contested areas, including the Emerald Triangle (Mom Bei), and the Ta Moan Thom, Ta Moan Tauch, and Ta Krabei temples.
Despite the ICJ’s clarifications and Cambodia’s renewed call for judicial intervention, nationalist sentiments on both sides continue to fuel tensions, marking today's escalation as a dangerous new chapter.
Conflict highlights Thailand's political struggle and Hun Sen influence
The border crisis has unfolded amidst significant political instability within Thailand, while former Cambodian leader Hun Sen continues to exert considerable influence.
In Thailand, Prime Minister Paetongtarn Shinawatra is facing intense scrutiny and was recently suspended from office over an ethics probe linked to her handling of the crisis. A leaked phone call between her and former Cambodian leader Hun Sen, in which she reportedly called him "uncle" and dismissed a Thai commander, has further inflamed domestic divisions.
Thai Prime Minister Paetongtarn Shinawatra (left) with Indonesian President Prabowo Subianto Djojohadikusumo earlier this year
Critics accuse her of undermining the military, and a key coalition partner has since exited her government, adding to the fragility of her administration.
Despite stepping down as Prime Minister last year, Hun Sen continues to shape Cambodian affairs and its stance on the border dispute. His close ties with Prime Minister Paetongtarn Shinawatra, as evidenced by the leaked phone call, highlight his ongoing role in shaping Cambodia's foreign policy, even as his son, Hun Manet, now holds the premiership.
Hun Sen has publicly defended Cambodia's actions and condemned Thailand's "aggression," reinforcing a hardline approach to the border issue. Cambodia's recent announcement to revive mandatory military conscription, to be implemented next year, further underscores its preparedness for military confrontation.
Ceasefire agreed
On Monday July 28, Malaysia, who hosted the peace talks and acted as mediator in its role as the current ASEAN chair, announced an “immediate and unconditional” ceasefire had been reached.
Both Cambodian Prime Minister Hun Manet and Thai Acting Prime Minister Phumtham Wechayachai were in attendance.
Ambassadors from the United States and China also participated as co-facilitators, with US President Donald Trump reportedly exerting pressure on both nations to halt the fighting – warning that continued hostilities could jeopardise future trade deals. Under his "reciprocal tariffs" policy, as of early August, both Thailand and Cambodia were subject to a 36 percent tariff on exports to the US.
Malaysian Prime Minister Anwar Ibrahim hailed the outcome, stating: “This is a vital first step towards de-escalation and the restoration of peace and security in the region. We are prepared to coordinate a monitoring team to verify and ensure that the ceasefire agreement is upheld.”
Malaysia urged Cambodian PM Hun Manet and Thai Acting PM Phumtham Wechayachai to stand down and de-escalate tensions
Cambodian Prime Minister Hun Manet expressed deep gratitude for the international support. “Today we had a very good meeting and very good results ... to stop immediately the fighting that has caused many lives lost, injuries and also caused displacement of people,” he said. He specifically thanked “President Donald Trump for his decisive role in paving the way for these talks and the ceasefire. "His personal involvement was crucial.”
Hun Manet also acknowledged Beijing’s role, adding: “We also appreciate the support and presence of our friends from China, who have consistently advocated for peaceful resolution in our region.”
In a separate social media post, Hun Manet shared that Trump had personally called him after the talks to offer congratulations on the success of the ceasefire negotiations.
“His Excellency understands that in order for this agreement to be fully implemented and sustainable, there is a need for a mechanism to closely monitor the performance of stakeholders, which is also a point of consensus at the special meeting,” Hun Manet said.
“In this sense, H.E. the President has agreed to engage the United States in monitoring the implementation of the Ceasefire Agreement and continue to cooperate with mechanisms prepared by Malaysia for the successful monitoring,” he added.
I have just spoken to the Acting Prime Minister of Thailand, and it was a very good conversation. Thailand, like Cambodia, wants to have an immediate ceasefire, and PEACE. I am now going to relay that message back to the Prime Minister of Cambodia. After speaking to both Parties, Ceasefire, Peace, and Prosperity seems to be natural. We will soon see!
President Donald Trump on Truth Social
Thai Acting Prime Minister Phumtham Wechayachai affirmed Thailand’s commitment to the truce, despite earlier reservations about Cambodia’s sincerity. “This outcome reflects Thailand’s desire for a peaceful resolution,” he said, emphasising that the ceasefire would “be carried out successfully in good faith by both sides.” Phumtham later revealed that President Trump had also called him to express congratulations and confirmed that ongoing trade talks with Washington regarding tariff levels could now proceed favourably.
As part of the ceasefire agreement, military commanders from both countries are expected to meet today, July 29, to discuss de-escalation. Cambodia will host a border committee meeting on August 4. In addition, the foreign and defence ministers of Malaysia, Cambodia, and Thailand have been tasked with developing a detailed mechanism to implement and monitor the ceasefire.
Deal comes amid doubts over ASEAN’s effectiveness
The ongoing border clashes between Thailand and Cambodia have placed the Association of Southeast Asian Nations (ASEAN) under a critical spotlight, with experts debating its effectiveness in resolving internal disputes. While many argue that ASEAN's role is more vital than ever in de-escalating tensions, the current crisis also starkly exposes the limitations posed by its long-standing principle of non-interference.
The leaders of the Association of Southeast Asian Nations pose for a group photo at the ASEAN Summit in Kuala Lumpur in May
ASEAN's foundational commitment to non-interference in the internal affairs of member states is a double-edged sword. While it promotes respect for sovereignty, it can also restrict the bloc’s ability to act decisively in situations like the Thai-Cambodian conflict.
Analysts note that ASEAN’s institutional structure and the lack of trust between the parties involved often prevent it from assuming a direct mediating role unless both countries formally request its assistance. Cambodia’s earlier appeal for UN intervention – echoing a similar move in 2011 – underscores a troubling lack of confidence in ASEAN’s capacity to manage conflict within its own region.
Nonetheless, yesterday’s announcement shows that ASEAN can still play a critical role despite its limitations.
This article was first published on the Asia Media Centre website
The Foundation's Asia in Focus initiative publishes expert insights and analysis on issues across Asia, as well as New Zealand’s evolving relationship with the region.
