Mediation with Chinese characteristics in the 2025 Thailand–Cambodia border crisis
In Brief
On 26 October 2025, Thailand and Cambodia signed a Joint Peace Statement to resolve their renewed border conflict. While the United States was present at the formal signing through the attendance of President Donald Trump, China was absent. Later, President Xi Jinping publicly affirmed that China had contributed significantly to the crisis’s resolution. His remarks helped clarify China’s role in the mediation process and reflected Beijing’s desire to publicise its efforts.
Understanding how the conflict unfolded and why external mediation became necessary is essential. On 24 July 2025, a military clash erupted along the Thailand–Cambodia border due to longstanding territorial disputes, killing at least 38 people and displacing over 300,000 civilians. In response, on 28 July, Malaysia — serving as ASEAN’s rotating chair — convened a special meeting between Cambodian Prime Minister Hun Manet and Thailand’s then-acting prime minister Phumtham Wechayachai, brokering an initial ceasefire.
Despite the dispute’s longstanding territorial origins, its rapid escalation exposed the complexities of contemporary regional governance. ASEAN Secretary-General Kao Kim Hourn admitted in September 2025 that the conflict’s sudden escalation ‘caught ASEAN by surprise,’ underscoring the bloc’s structural weaknesses in crisis prevention and coordination.
While ASEAN provided the political framework for dialogue, the ceasefire’s implementation and reinforcement required external support — the mediation efforts of China and the United States proved decisive. Yet their respective approaches differed significantly: Washington relied on high-level political pressure and overt intervention to expedite cessation of hostilities, while Beijing engaged in low-profile diplomacy and institutional mediation to restore bilateral dialogue and trust. This contrast highlights the evolving challenge for Southeast Asian states in maintaining equilibrium amid intensifying major-power dynamics.
Understanding China’s role necessitates looking at how it structured its diplomatic response, defined by backstage coordination and mechanism embedding. On 30 July, China hosted an informal trilateral consultation with Cambodia and Thailand in Shanghai. In the following weeks, Foreign Minister Wang Yi held separate meetings with both the Thai and Cambodian foreign ministers and with ASEAN Secretary-General Kao Kim Hourn. The Ministry of Foreign Affairs’ Special Envoy for Asian Affairs, Deng Xijun, conducted multiple rounds of shuttle diplomacy in September to reinforce commitment to the ceasefire.
These engagements demonstrated China’s effort — while maintaining its non-interference principle — to use institutional channels and quiet diplomacy to steer both parties back toward bilateral negotiation within the ASEAN framework. This approach reflected a ‘mechanism-based, dialogue-oriented’ philosophy that prioritised process management and stability restoration.
Differences in Chinese and US approaches to advancing the ceasefire and subsequent talks reveal their polarised strategic logics. The US approach — with its high-level political pressure — sought rapid and visible de-escalation. China emphasised long-term trust-building and procedural continuity through discreet diplomacy and regional institutions. While the former produced quick outcomes with limited structural depth, the latter offered gradual but potentially more sustainable progress.
US mediation basically focused on speed and pressure, while China’s model was anchored in stability and persistence. These modalities were not contradictory but functionally complementary. Washington’s assertive engagement helped halt violence in the short term, while Beijing’s constructive engagement reinforced mechanisms for lasting peace.
External involvement remains both essential and sensitive in the context of regional stability. Southeast Asian states have long prioritised autonomy and are naturally cautious about any outside engagement that could be interpreted as major-power intrusion or undermine ASEAN centrality. This sensitivity reflects broader regional hedging behaviour, as governments seek to avoid being pulled into great-power rivalry even when external mediation is necessary. Yet ASEAN’s mechanisms — though central to regional diplomacy — often lack the speed and enforcement capacity required to manage fast-moving or deeply rooted territorial disputes.
The challenge lies in managing how external actors engage constructively within regional frameworks. While the United States and China acted independently — with different motives and methods — some analysts argue that Beijing and Washington’s distinct forms of engagement nonetheless had cumulative effects on the pathway toward de-escalation.
China’s mediation model emphasised non-confrontation, relationship repair and institutional embedding. Beijing sought to advance a moderate and process-oriented approach to crisis management through deferential methods. While the effect of this constructive engagement was necessarily limited — given that both disputants continued to issue competing diplomatic signals and that Thailand’s military significantly influenced crisis decision-making — China’s efforts nonetheless helped maintain open communication channels and prevent further escalation. Deepening China–Thailand defence exchanges also help form the broader context in which Beijing’s diplomatic messages were received.
Beyond immediate crisis management, transparency remains central to China’s evolving regional role. While China traditionally favours low-profile diplomacy, calibrated openness — such as joint statements issued through ASEAN — could help strengthen external confidence in its intentions and reduce scepticism about backroom deals. A more visible record of China’s crisis diplomacy would not only reinforce Beijing’s desired narrative as a constructive regional stabiliser but also show alignment with ASEAN-led processes.
In a region where perceptions often shape outcomes as much as material capabilities, such transparency can help ensure that major-power involvement supports — rather than complicates — local efforts to maintain peace. China’s ability to pair quiet mediation with selective openness will be essential for consolidating its role in regional security and for contributing to a more predictable and resilient peace along the Thailand–Cambodia border and beyond.
Bo Ma is Associate Professor at the School of International Studies and Deputy Director of the China Center for Collaborative Study of the South China Sea at Nanjing University.
Zining Xu is Research Officer at the School of International Studies at Nanjing University.