Japan’s Latest Chapter in Military Cooperation: Official Security Alliance (OSA)

Japan and Southeast Asia have shared a robust connection historically; however, the dynamics of their relationship are undergoing a shift. Calling the Japan-ASEAN relationship a “Golden Friendship”, the Kishida Administration has strengthened their connectivity in a wide range of fields, including infrastructure development, digital connectivity, supply chain resilience, human and knowledge connectivity, and so forth. In November, the Japanese government finalized several agreements with Southeast Asian countries. Specifically, Prime Minister Kishida agreed to supply four patrol boats, intended for monitoring, surveillance, and disaster relief to the Bangladesh Navy. Vietnam and Japan issued a joint statement that announced the provision of defense equipment and technology transfers to Vietnam. During Kishida’s visit to the Philippines, President Ferdinand Marcos, Jr. and Kishida concluded several agreements, including a 600 million yen grant to provide coastal radar systems to the Armed Forces of the Philippines. Aid related to the military was previously prohibited for Japan due to ODA (Official Development Assistance) restrictions. However, the newly introduced framework, distinct from ODA, empowers Japan to offer military aid, fostering stronger security cooperation with Southeast Asian countries.

Establishing a new framework for military aid: OSA (Official Security Assistance)

In April 2023, Japan introduced a new cooperation framework called “Official Security Assistance” (OSA), aimed at benefiting the armed forces and related organizations of developing countries in terms of security cooperation. Through OSA, Japan can offer equipment and supplies as well as assistance for infrastructure development to even the military of developing countries, enhancing their security capacities. The recipient countries are limited to “like-minded countries,” which are the Philippines, Malaysia, Bangladesh, and Fiji, in its first fiscal year, FY2023. OSA operates within the range of Three Principles on Transfer of Defense Equipment and Technology, effectively banning the export of potentially lethal equipment. Nonetheless, OSA could potentially have a significant impact.

Historically, Japan is a large contributor to ODA, with a substantial portion of the funds directed towards Southeast Asia. On the other hand, it has been questioned whether ODA is strategically operated to benefit Japan itself. ODA is provided to all low- and middle-income countries for social and economic development. Notably, Japanese ODA has operated under a request-based system. Consequently, Japan has refrained from providing assistance through ODA in cases where such support could potentially aid the recipient countries’ militaries. Nor was the notion that Japan would provide ODA to a country because it was important to Japan. These perspectives gradually shifted with the revision of Japan’s Development Cooperation Charter in June 2023, introducing offer-type assistance. Nonetheless, Japan decided to take it a step further by committing to additional types of support through OSA which covers the gap of ODA.

As of November 2023, two projects are underway in Bangladesh and the Philippines through OSA. While the budget of OSA is not as substantial as ODA, set at two billion Yen (15 million USD) for FY 2023, the Ministry of Foreign Affairs reportedly aims to increase its budget to five billion Yen (15 million USD) in FY2024. Additionally, recipient countries are likely to expand to include Indonesia, Mongolia, Djibouti, and other countries in 2024.

The aim of creating the OSA

The decision to introduce OSA follows Japan's announcement in December 2022, where it unveiled that it would double defense spending over five years in response to China's growing military might. Japan’s National Security Strategy (NSS), approved in December 2022, marks the first document proposing the concept of OSA. Describing the current security environment as “severe and complex as it has ever been since the end of World War II,” the NSS positions OSA as “part of the efforts to reinforce the comprehensive defense architecture.” Current global instability, including the rise of China, the Russia-Ukraine War, turbulence in the Taiwan Strait, and the recent Hamas-Israel conflict, made the government determined to shift its development policy.

Looking at the countries specified as OSA destinations, the aim of OSA becomes more obvious. The Philippines and Vietnam have faced direct threats from China’s attempt to expand its marital territory in the South China Sea. Bangladesh imports roughly 70% of its weapons from China, however, aims to diversify suppliers. In light of the above, OSA has multiple aims: 1) to strengthen Japan's deterrence against China by increasing its presence in the Indo-Pacific area, 2) to enhance the defense capabilities of the countries receiving assistance so that they can counter the threat, and 3) to reduce their dependence on China by getting them to accept assistance from Japan. As OSA extends to more countries and combines other initiatives such as the Japan-US alliance, it may have multifaceted implications, including the potential enhancement of supply chains and the securing of intelligence and so forth.


Examining Japan’s development cooperation provides insights into the nation’s foreign policy within a broader context. In the postwar era, development cooperation played a crucial role in rebuilding relationships with neighboring countries. As Japan’s economy grew, it became a tool for creating an enabling environment for companies to expand in Asia. After the Cold War, it served to improve governance in recipient countries, especially those transitioning from socialist regimes. In the 2000s, amid China’s rise, it contributed to the development of legal and judicial systems and the consolidation of democracy, primarily in Asian nations. Now, we observe Japan’s intention to expand its security network by leveraging the OSA in the Indo-Pacific region. The underlying foreign policy of the Kishida administration recognizes that “the international community now stands at a historic crossroads” at the end of the post-Cold War era, and OSA symbolizes a significant transformation chosen by Japan to address these challenges.

Momo Shioyama is a research intern with the Japan Chair at the Center for Strategic and International Studies (CSIS).

Momo Shioyama

Research Intern, Japan Chair