The strategic dynamics along the Mekong River are undergoing a noticeable shift, primarily driven by the evolving relationships between Cambodia and Vietnam. Recent diplomatic exchanges, culminating in a video call between Cambodian Deputy Prime Minister PRAK Sokhonn and the acting Foreign Minister of Vietnam, Le Hoai Trung, on September 11, 2025, reveal a complex interplay of economic interests, regional security concerns, and the pursuit of stability within the Association of Southeast Nations (ASEAN). This realignment demands careful scrutiny given the Mekong’s vital role as a source of water, transportation, and livelihood for a vast swathe of Southeast Asia. The call underscored a desire for expanded engagement, specifically the upcoming 21st Meeting of the Cambodia-Vietnam Joint Commission, but also highlighted simmering tensions relating to resource management and regional security.
The context for this latest exchange is rooted in a history of deeply intertwined economic and political ties. Cambodia’s reliance on Vietnam for trade, particularly in consumer goods and manufacturing, has intensified over the past decade, creating a significant economic interdependence. Vietnam represents Cambodia’s largest trading partner, accounting for over 30% of Cambodian exports in 2023. However, this relationship is not without its challenges. Vietnam’s dominance in the trade balance has fueled concerns within Phnom Penh regarding over-reliance and potential vulnerabilities. Simultaneously, Vietnam’s own economic growth, powered largely by its robust manufacturing sector, has presented opportunities for investment and technical assistance within Cambodia. The push for diversification and value-added industries in Cambodia is, in part, a response to this asymmetrical dependence.
Recent developments regarding the Cambodia-Thailand border conflict provide further critical context. Tensions stemming from disputed demarcation claims have, for years, been a persistent source of instability along the 1,270-kilometer border. The Special General Border Committee meeting in Koh Kong Province on September 10th, 2025, facilitated by Cambodian Prime Minister Hun Sen, resulted in “encouraging outcomes” according to official statements, primarily a continued commitment to a ceasefire agreement. Vietnam’s consistent support for this agreement – including its contribution to the Interim Observer Team – is a key element in stabilizing the region. However, the underlying territorial disputes remain a potent factor, potentially creating opportunities for external actors to exploit divisions. “The continued calm is, undeniably, a significant achievement, but the fundamental issues remain unresolved,” commented Dr. Nguyen Anh Duc, Senior Research Fellow at the Vietnam Institute of Strategic Studies. “Vietnam’s engagement reflects a pragmatic approach – maintaining stability while simultaneously pursuing its own strategic objectives within the Mekong region.”
Furthermore, the focus on regional security, subtly woven into the conversation between Sokhonn and Hoai Trung, is significant. The ongoing tensions within Myanmar, characterized by civil conflict and humanitarian crises, are impacting regional security dynamics, with potential ramifications for bordering states like Cambodia and Vietnam. The ASEAN’s response to this situation – largely hampered by divisions among member states – further underscores the complexities involved. “The shared concern over Myanmar is undoubtedly a catalyst for closer cooperation between Cambodia and Vietnam, particularly in the realm of conflict resolution and humanitarian assistance,” stated Professor Le Thanh Hai, a specialist in Southeast Asian security at the National Institute of Policy and Strategy in Hanoi. “Vietnam’s engagement with Cambodia on this issue signals a broader trend of regional actors working together to address shared challenges.”
Looking ahead, short-term (next 6 months) outcomes likely include increased engagement between the two nations on trade diversification initiatives and the convening of the 21st Cambodia-Vietnam Joint Commission. This commission, responsible for managing the bilateral relationship, is expected to focus on resolving existing trade imbalances and identifying new areas of cooperation. Longer-term (5-10 years), the potential for a more integrated economic zone along the Mekong River is conceivable, contingent upon the resolution of outstanding border disputes and broader regional stability. However, sustained geopolitical competition, particularly from China, remains a significant factor. The ongoing struggle for influence in the Mekong basin, exemplified by China’s Belt and Road Initiative, presents a persistent challenge.
The shifting currents of the Mekong River are inextricably linked to the evolving dynamics between Cambodia and Vietnam. While the video call highlights a desire for enhanced cooperation, the underlying geopolitical realities – fueled by economic interdependence, regional instability, and external competition – demand ongoing observation and strategic assessment. The question remains: can Cambodia and Vietnam forge a truly sustainable partnership, or will the forces of power and scarcity continue to drive a more transactional and ultimately, more precarious relationship? The answer will have profound implications for the stability of Southeast Asia.