No Longer A Two-Nation War: External Pressures on Thailand and Cambodia for Peace in the Longstanding Thailand-Cambodia Border Dispute By: Samantha Luckham

The Thailand-Cambodia Border Dispute

The ongoing dispute between Thailand and Cambodia is not a recent development but rather a conflict rooted in more than a century of contested boundaries.[1] This dispute erupted back in 1907 during the French colonial rule in Cambodia, when border lines were delineated between Cambodia and Thailand.[2] This nearly 500-mile-long border is home to centuries-old temples, which both countries claim as their own.[3] Recently, this dispute has reared its head over the Preah Vihear temple on May 28th, 2025, leading to “the bloodiest Thailand-Cambodia border conflict in over a decade.”[4] As armed clashes arose across several areas along the frontier, a ceasefire was finally brokered on July 28th and reinforced on October 26th through Thailand and Cambodia signing the Kuala Lumpur Peace Accord.[5]

However, this ceasefire was deemed to only be temporary, as Thailand approved a temporary suspension of the ceasefire after four Thai soldiers were wounded in an explosion by a landmine along the border.[6] Even though Cambodia has stated that these landmines were from an old minefield, Thai military officials have doubts, believing that these landmines had been recently placed in the area where Thai military conduct regular patrols.[7] This threat of a permanent breakdown of the ceasefire is alarming, given that only five days of fighting in late July of this year resulted in at least 48 fatalities and the displacement of nearly 300,000 people.[8] Thailand additionally halted the release of 18 Cambodian prisoners of war, calling Cambodia’s explanation of the landmine incident as “insufficient.”[9] Ultimately, the initial ceasefire and pressure to continue the ceasefire is not brought by the people of Thailand and Cambodia, but rather external pressures on these countries.[10] Both external and internal pressures need to be considered to broker an effective ceasefire agreement that both countries will follow.[11]

External Pressures for Peace

Notably, the United States has played a particularly assertive role in attempting to broker peace between Thailand and Cambodia.[12] Towards the end of July 2025, a frustrated U.S. President, Donald Trump, took to speaking with the Cambodia’s Prime Minister and Thailand’s Prime minister to try and broker peace, framing their peace as crucial to negotiate trade agreements with the United States.[13] Trump even went as far as threatening both countries with a 36% tariff on their exports, which would be set to take place if fighting continues.[14] These tariffs can have devastating effects for both countries, as exports to the United States represent 12% of Thailand’s GDP and 27% of Cambodia’s. This tariff on Thailand alone could cost them up to 1.23 trillion baht (almost 37.9 billion USD) and have significant impacts on exports, domestic supply chains, and labor and consumption.[15]

China has also sought to influence Thailand and Cambodia to resolve their dispute, albeit by less confrontational means.[16] China offered to play a “constructive role” in resolving the border dispute between the two countries, emphasizing that they would maintain an “objective and fair” position.[17] Chinese Foreign Minister Wang Yi also met with the Thai and Cambodian Foreign Ministers separately over the summer but also facilitated a three-way conversation in China.[18] China has also pledged to provide about 20 million yuan (about $2.8 million USD) of humanitarian aid to assist those affected in the recent border dispute.[19] Seeming to stray from their “objective and fair position” China’s leader further pledged to support Cambodia in advancing their self-sufficiency and development efforts.[20] China’s efforts to put an end to this conflict may in part be due to their economic investment in the Mekong region.[21] This continued conflict threatens economic and infrastructure development in the subregion such as disrupting key Belt and Road corridors which link Kunming to Bangkok and China-funded industrial zones across Cambodia’s coast.[22] More than just economic interest, both the United States and China appear to have strategic interests in Thailand and Cambodia that could be at risk with the continued dispute.[23]

Japan also has an economic presence in Thailand and Cambodia that would benefit from peace between the two countries.[24] With factories in both Cambodia and Thailand, during this recent dispute at the border, Japan has had to resort to traveling via sea routes to keep connection between their factories, increasing costs and causing production delays.[25] While not as direct as China or the United States, Japan has tried to assist in settling the conflict by working with both countries to deescalate.[26]

Another influence, geographically closer to these disputing countries, is the Association of Southeast Asian Nations (ASEAN).[27] Specifically, Malaysia led the efforts to broker a ceasefire between the two countries as the chair of ASEAN.[28] Malaysia held the meeting on July 28th that led to the initial ceasefire, notably attended by senior officials from China and the United States.[29]  Additionally, as part of the ceasefire framework, both parties agreed to keep open lines of communication between their local military commanders and senior officials and to accept a Malaysian-led ASEAN observer mission composed of defense attachés from the member states.[30]

Conclusion

These external pressures on Thailand and Cambodia to adhere to the ceasefire have no signs of stopping, and these countries needs to think about potential consequences to their people and economy if they continue to fight with each other.[31] However, this is a double edged sword as countries/groups exerting these external pressures to resolve this conflict must also understand the root cause of the dispute to obtain a ceasefire that will be durable.[32] Any future ceasefire agreement will simply be another band aid on this century old feud put in place by other countries unless the root issue of this dispute is addressed.[33]

[1] Yashraj Sharma, What’s in the Thai-Cambodia Peace Agreement and Can it Hold? Al Jazeera (Oct. 27, 2025), https://www.aljazeera.com/news/2025/10/27/whats-in-the-thai-cambodia-peace-agreement-and-can-it-hold.

[2] Id.

[3] Id.

[4]  Ryan Claffey, Thailand-Cambodia Border Agreement on Shaky Ground, East Asia Forum (Nov. 19, 2025), https://eastasiaforum.org/2025/11/19/thailand-cambodia-border-agreement-on-shaky-ground.

[5] Id.

[6] Cambodia Denies Thai Landmine Claims as Truce Hangs in the Balance, Al Jazeera (Nov. 11, 2025), https://www.aljazeera.com/news/2025/11/11/cambodia-denies-thai-landmine-claims-as-truce-hangs-in-the-balance.

[7] Id.

[8] Id.

[9] Id.

[10] Oliver Holmes, Trump Pressures Thailand to Recommit to Cambodia Ceasefire with ‘Threat of Tariffs,’ The Guardian (Nov. 15, 2025), https://www.theguardian.com/world/2025/nov/15/us-pressures-thailand-to-recommit-to-cambodia-ceasefire-with-threat-of-tariffs.

[11] See generally Claffey, supra note 4.

[12] Id.  

[13] Id.

[14] Id.

[15] Trump’s 36% Tariff a Disaster for Thai Economy, Banks Warn of Ripple Effect Across Sectors, The Nation (Nov. 17, 2025), https://www.nationthailand.com/business/economy/40052697.

[16] China Offers to Help Resolve Thailand, Cambodia Border Dispute, Reuters (July 11, 2025), https://www.reuters.com/world/china/china-offers-help-resolve-thailand-cambodia-border-dispute-2025-07-11.

[17] Id.

[18] Liz Lee & Shi Bu, China Urgers Thailand, Cambodia Reconciliation in Three-way Talks, Reuters (Aug. 14, 2025), https://www.reuters.com/world/china/china-urges-thailand-cambodia-reconciliation-three-way-talks-2025-08-14.

[19] China Announces Humanitarian Support of 20 Million Yuan to Cambodia, Khmer Times (Sept. 2, 2025), https://www.khmertimeskh.com/501749799/china-announces-humanitarian-support-of-20-million-yuan-to-cambodia.

[20] Id.

[21] Pongphisoot (Paul) Busbarat, China’s Mediation Offer in the Thailand-Cambodia Border Dispute Sheds Light on Beijing’s Security Role in Southeast Asia, Carnegie (Aug. 6, 2025), https://carnegieendowment.org/posts/2025/08/chinas-mediation-offer-in-the-thailand-cambodia-border-dispute-sheds-light-on-beijings-security-role-in-southeast-asia?lang=en.

[22] Id.

[23] Morgan Michaels & Evan A. Laksmana, The Complex Fault Lines of the Thai-Cambodian Armed Conflict, IISS (Aug. 13, 2025), https://www.iiss.org/online-analysis/online-analysis/2025/08/the-complex-fault-lines-of-the-thaicambodian-armed-conflict.

[24] Kawashima Shin, Cambodia-Thailand Border Clashes: The Role of Supply Chains, The Diplomat (Aug. 12, 2025), https://thediplomat.com/2025/08/thailand-cambodia-border-clashes-the-role-of-supply-chains.

[25] Id.

[26] Id.

[27] Michaels & Laksmana, supra note 23.

[28] Id.

[29] Id.

[30] Id.

[31] Holmes, supra note 10.

[32] Claffey, supra note 4.

[33] See generally Michaels & Laksmana, supra note 23.