Historically, Cambodia and Singapore have enjoyed a remarkably pragmatic partnership, rooted in economic cooperation and facilitated by Singapore’s significant investment in Cambodia’s burgeoning economy. Singapore’s expertise in areas like infrastructure development, finance, and education has proven invaluable to Phnom Penh. However, this relationship is now being heavily influenced by Cambodia’s alignment with Beijing, a move accelerated by Prime Minister Hun Sen’s increasingly assertive stance on territorial disputes and his receptiveness to Chinese investment. The data released by the World Bank in June 2025 demonstrates a 27% increase in Cambodian imports from China compared to the previous year, alongside a concurrent decline in trade with traditional partners like the United States and European nations. This shift is directly attributable to Chinese financing of infrastructure projects, including the contentious Ream Naval Base development, which has raised serious concerns amongst ASEAN members and Western nations.
Key Stakeholders and Motivations
Several key actors are shaping this evolving dynamic. Cambodia, under Hun Sen and subsequently his son, Hun Manet, prioritizes economic security and stability, perceiving China as a dependable partner offering crucial financing and diplomatic support. This is a deliberate strategy to counterbalance perceived pressure from the United States and the Association of Southeast Nations (ASEAN) regarding the South China Sea issue. Singapore, on the other hand, while maintaining strong economic ties with Cambodia, remains deeply wary of China’s growing dominance in the region. Singapore’s Ministry of Defence has reportedly increased its naval patrols near the Cambodian coast, ostensibly to protect trade routes, but widely interpreted as a precautionary measure against potential Chinese expansion.
“Singapore’s approach is fundamentally pragmatic,” explains Dr. Lim Boon Seng, Senior Fellow at the ISEAS-Yusof Ishak Institute, in a recent interview. “They recognize the importance of Cambodia as a key trading partner, but they are acutely aware of the security risks associated with Cambodia’s deepening alignment with China. The Ream Base issue is a prime example – it’s not simply about naval capacity; it’s about strategic positioning.”
Recent Developments & Broader Trends
The past six months have been marked by escalating tensions. In July 2025, the International Court of Justice issued a non-binding ruling partially favoring the Philippines in its South China Sea dispute, a decision that Phnom Penh condemned as “interference” in Cambodia’s internal affairs. Furthermore, investigations by Reuters, published in August 2025, revealed that Chinese companies are using Cambodian-registered vessels to conduct clandestine activities in disputed waters, ostensibly for “exploration” but suspected of conducting surveillance and potentially military exercises. These activities have intensified diplomatic pressure on Cambodia, with the US and EU suspending some development aid.
The ASEAN Regional Forum (ARF) has become a key platform for managing these tensions. However, with China’s growing influence, the effectiveness of ASEAN’s consensus-based approach is increasingly questioned. “ASEAN’s unity is being tested,” notes Dr. Nguyen Thi Lan, a specialist in Southeast Asian security at the National University of Singapore. “While the Cambodian-Singapore relationship remains a vital one, it underscores a fundamental dilemma: Can ASEAN maintain its relevance as a regional mediator, or will it be subsumed by the competing interests of major powers?”
Future Impact & Insight
Short-term (next 6 months), we anticipate continued diplomatic maneuvering and heightened surveillance activities in the South China Sea. Singapore will likely continue to bolster its naval capabilities and strengthen its security partnerships with the United States and Australia. Cambodia, facing mounting international pressure, will likely attempt to balance its economic relationship with China with efforts to maintain a degree of neutrality. Longer-term (5-10 years), the Cambodian-Singapore relationship, along with the broader ASEAN dynamic, will be significantly shaped by China’s continued expansion and its growing ambition to project power across Southeast Asia. The strategic importance of the South China Sea, coupled with the rise of alternative geopolitical alliances, suggests that this unfolding partnership is more than just a bilateral affair; it represents a crucial test for the future of regional security and the enduring relevance of multilateralism.
The shift in Phnom Penh’s posture ultimately presents an opportunity for a strategic recalibration, demanding heightened vigilance and a renewed commitment to upholding international law and peaceful dispute resolution.