Cambodia’s Ream Naval Base hosted the Japanese Maritime Self-Defense Force (JMSDF) vessels Bungo and Etajima, in what was hailed as a goodwill visit. The event marked the first foreign naval presence at the newly upgraded base, following its formal inauguration by Cambodian Prime Minister Hun Manet and a high-level Chinese military delegation earlier in the month. The timing and geopolitical context, however, suggest the base is emerging as more than a local military upgrade—it’s fast becoming a focal point in the tug-of-war for influence in Southeast Asia.
The Japanese ships’ arrival came amid increasing scrutiny over China’s growing footprint at Ream. Though the visit was couched in the language of diplomacy and defense cooperation, Japan’s statement carried a clear subtext. Miyoshi Asagi, Counsellor at the Japanese Embassy in Phnom Penh, emphasized the “importance of freedom of navigation, free and open international order based on international law.” Coming from a country often at odds with Beijing’s assertive maritime claims in the South China Sea and East China Sea, it was a diplomatic shot across the bow.
Japan’s inclusion on the guest list—especially as the first foreign navy to dock at Ream since its upgradation—gave Cambodia’s government a moment to rebuff accusations that the base is evolving into a de facto Chinese military outpost. But Japan’s symbolic presence doesn’t erase concerns from regional observers and Western governments who fear that Cambodia is inching ever closer to China’s strategic orbit.
The upgrades at Ream, heavily funded by China, are sweeping. Completed between 2022 and early 2025, the renovations include a 300-meter-long deep-water pier, a 5,000-ton dry dock, a 1,000-ton slipway, and new administrative and logistical facilities. Central among these is the Cambodia-China Joint Logistics and Training Center—an innocuous name that masks potentially profound implications.
During the inauguration, Prime Minister Hun Manet took pains to assure observers that “Cambodia has nothing to hide.” He insisted the base would remain open to other countries and denied any exclusive access arrangement with Beijing. “We have no intention—whether in the past, present, or future—of violating our own constitution by allowing any country or military to establish an exclusive base on Cambodian soil,” he declared.
Despite such assurances, military analysts argue that presence does not need to be “exclusive” to be strategic. Even a limited Chinese presence at Ream—especially one backed by modern logistics and regular joint exercises—can tip the scales of regional security.
Beijing’s maritime strategy has always leaned heavily on the development of dual-use infrastructure—projects that ostensibly serve civilian needs but are built to military standards and capable of hosting armed forces when required. The Ream Naval Base is now seen as a textbook case.
The “civil-military fusion” model promoted by Chinese President Xi Jinping encourages precisely this kind of layered investment. In Cambodia, Beijing has embedded itself in a wide array of infrastructure initiatives under the Belt and Road Initiative (BRI), including the Dara Sakor International Airport—with a runway long enough to accommodate military aircraft—Kampot Logistics and Port, the Phnom Penh-Sihanoukville Expressway, and the Mekong canal project.
Research by the Observer Research Foundation indicates that more than $9.6 billion of the $15 billion China has invested in Cambodia under BRI adheres to dual-use construction principles. These projects, while nominally commercial, provide critical infrastructure Beijing could leverage in a crisis.
First, geography. Situated along Cambodia’s southern coast near the Gulf of Thailand, the base provides direct access to the South China Sea and a line of sight to southern Vietnam—territory long at the center of regional maritime disputes. From Ream, Chinese systems could monitor U.S., Vietnamese, and other regional naval activity. With the right radar and surveillance equipment, intelligence collection could be low-profile but high-yield.
Second, logistics. The Malacca Strait—through which 80% of China’s oil and gas imports pass—is just over 1,000 kilometers away. A base at Ream allows Beijing to support naval operations near this critical chokepoint. In the event of a regional crisis, it provides an opportunity to deploy PLAN vessels rapidly to seal or defend this narrow sea lane, disrupting adversary reinforcements or securing energy supply lines.
Third, training and interoperability. The Joint Logistics and Training Center will reportedly be used for regular exercises like the annual Golden Dragon drills. Though billed as disaster relief and peacekeeping training, these events serve to embed Chinese doctrine within Cambodian forces and give the PLA a forward-operating familiarity with the local environment.
According to Zhang Junshe, a Chinese military expert quoted in China’s state-run Global Times, the center will “enhance coordinated military operation capabilities,” suggesting that the collaboration is more than superficial.
The Cambodian government continues to insist it is not violating its own constitution, which forbids hosting foreign military bases. Officials argue that Ream will remain under Cambodian control and open to all. But international trust is fragile.
The first red flags were raised in 2019, when The Wall Street Journal cited unnamed U.S. officials claiming a secret agreement gave China access to the base for 30 years. Though Cambodia dismissed the report as misinformation, subsequent developments have fueled the perception that the deal, whether formalized or not, is in effect.
Further straining Cambodia’s credibility was its decision to demolish U.S.-funded buildings at Ream in 2020 as part of the Chinese-sponsored upgrade. A U.S. defense attaché was denied full access during a visit in 2021. Washington took note. Since then, military ties between Cambodia and the United States have eroded.
Meanwhile, China’s support has remained steadfast. It’s a mutually beneficial relationship: Cambodia gets investment, infrastructure, and political backing; China gains a maritime foothold near one of the world’s most strategic waterways.
China’s interest in Ream is not an isolated case. It fits a wider pattern.
Across the Indo-Pacific and into Africa, Beijing has either constructed or gained access to a string of dual-use ports and logistical hubs. From Djibouti on the Horn of Africa (China’s only official overseas military base), to Gwadar in Pakistan, Hambantota in Sri Lanka, and potentially Bata in Equatorial Guinea, China is methodically expanding its “string of pearls”—a network of maritime facilities that can support PLAN operations far from home.
Each port serves three key purposes: power projection, intelligence gathering, and rapid deployment. Collectively, they serve as a scaffold for China’s future ambitions to transform the PLA Navy into a true Blue Water Navy capable of sustained global presence.
Compared to the U.S., which operates hundreds of overseas bases, China’s network is nascent. But it’s growing—and each node strengthens Beijing’s leverage.
The strategic tilt of Ream has not gone unnoticed in Hanoi. Vietnam, which shares a long and often tense border with China and disputes Beijing’s expansive South China Sea claims, is wary of any Chinese military encroachment nearby. A Chinese presence at Ream would allow surveillance over Vietnam’s southern coastline and potentially disrupt Hanoi’s own maritime operations.
The U.S. is also concerned. A 2022 U.S. State Department report warned of the implications of “unverified” Chinese military access to Ream. Though diplomatic engagements continue, the trajectory of Cambodia’s defense posture appears increasingly China-aligned.
Even within ASEAN, the Ream base risks sowing division. While Cambodia remains closely tied to Beijing, other member states—particularly the Philippines and Vietnam—have grown more vocal in opposing Chinese actions in the South China Sea. Ream may deepen existing fissures in ASEAN’s collective security outlook.
For now, the presence of Japanese ships at Ream provides Cambodia a temporary shield against criticism that the base is exclusively Chinese. But symbolic port calls won’t change the deeper dynamics. The base, its design, its partnerships, and its operational rhythm all suggest a tilt toward Chinese strategic preferences.
Unless significant transparency measures are adopted—such as regular third-party inspections, open-access scheduling, or multilateral agreements on use—the perception of Ream as a Chinese satellite will persist.
For China, Ream is a quiet but potent strategic win. For Japan, the U.S., and other regional players, it is a wake-up call.
In an age where bases no longer need to wear the badge of exclusivity to be powerful tools of influence, Ream represents the new frontier in China’s maritime strategy: access without ownership, presence without provocation.
