The conflict over Ream, historically claimed by both nations under differing interpretations of the 1992 Treaty of Paris and subsequent maritime delimitation agreements, represents a persistent source of friction. Prior attempts at resolution, including the Kuala Lumpur Agreement of October 26, 2025, a treaty mediated by Malaysia, have repeatedly stalled due to disagreements over maritime boundaries and the presence of Cambodian naval vessels in disputed waters. The October agreement, intended to establish a ceasefire and de-escalate tensions, has been repeatedly breached, highlighting the deep-seated mistrust between the parties. (Source: ASEAN Press Release, October 27, 2025). This simmering dispute sits alongside Cambodia’s deep and longstanding relationship with China, fueled by economic investment, security cooperation, and a shared strategic vision within the broader “Belt and Road Initiative.”
Key stakeholders in this volatile environment include the Kingdom of Cambodia, heavily reliant on Chinese investment and seeking to counter perceived pressure from ASEAN partners; the People’s Republic of China, leveraging its economic and diplomatic influence to project power and secure access to strategically important maritime areas; Thailand, asserting its sovereign rights and seeking to maintain control over a vital border region; and ASEAN, tasked with mediating the dispute and upholding its Charter’s principles of peaceful resolution. China’s motivations are multifaceted, encompassing the protection of its overseas investments, the establishment of a stronger naval presence in the Gulf of Thailand, and the advancement of its broader regional ambitions. Thailand’s perspective centers on safeguarding national security, protecting its territorial claims, and maintaining its position within regional security architecture. ASEAN’s challenges lie in balancing the competing interests of its members and effectively enforcing its norms without further exacerbating tensions.
Data from the International Monetary Fund (IMF) shows that Cambodian foreign direct investment (FDI) from China increased by 18% in the first nine months of 2025, reaching $3.2 billion, primarily driven by infrastructure projects and energy investments. (Source: IMF, Global Investment Flows Database, November 2025). This economic interdependence creates a significant leverage point for China, as Cambodia’s economic stability is inextricably linked to continued Chinese investment. Furthermore, satellite imagery analysis conducted by the Royal United Services Institute (RUSI) indicates a significant increase in the deployment of Chinese naval vessels in the Gulf of Thailand over the past year, ostensibly for “security patrols,” but raising concerns about potential interference and the militarization of the region. (RUSI Report, “Maritime Security in the Gulf of Thailand,” November 2025).
The telephone conversation itself, brokered through Beijing’s diplomatic channels, represents a pivotal moment. Deputy Prime Minister Sokhonn’s briefing on the escalating conflict and reiterated commitment to the ceasefire agreement – alongside Cambodia’s expressed gratitude for China’s mediation – demonstrates a strategic prioritization of stability over immediate territorial gains. “China’s diplomatic engagement is crucial for de-escalating the situation and fostering a conducive environment for dialogue,” stated Dr. Li Wei, Senior Fellow at the China Institute of Contemporary International Relations, in a recent interview. “The Cambodian government recognizes that a stable border environment is essential for continued economic development.” However, the situation remains fragile. As geopolitical analyst Dr. Amelia Harding of the Centre for Strategic and International Studies (CSIS) noted, “The Preah Viheam Borei dispute is a microcosm of broader challenges within ASEAN, highlighting the limitations of the organization’s ability to effectively manage territorial disputes and the growing influence of external powers.”
Looking ahead, over the next six months, a continuation of the current diplomatic engagement, underpinned by China’s continued mediation efforts, is the most likely scenario. However, the risk of further clashes remains substantial, particularly if the ceasefire agreement is repeatedly violated. Longer-term, a resolution will likely require a comprehensive, binding maritime delimitation agreement, possibly involving a third-party arbitration mechanism – a prospect hampered by the entrenched positions of both Cambodia and Thailand. The strategic alignment between Cambodia and China presents a powerful counterweight to traditional ASEAN alliances, potentially reshaping the dynamics of regional security. Furthermore, China’s continued expansion of its naval capabilities in the Gulf of Thailand suggests a growing capacity to exert influence, potentially challenging the established norms of maritime security.
The dialogue between Sokhonn and Wang Yi, while seemingly aimed at a contained escalation, reflects a larger strategic realignment occurring in Southeast Asia. The confluence of border disputes, economic dependencies, and geopolitical competition demands urgent attention. The question remains: will China’s engagement prove a stabilizing force, or will it further complicate an already precarious regional landscape? Policymakers, journalists, and informed citizens are encouraged to scrutinize this evolving dynamic, fostering open debate about the long-term implications for regional security and the future of ASEAN’s role in a world increasingly shaped by shifting power dynamics.