Indonesia and Japan are accelerating a shared strategic defense agenda, translating high-level dialogue into capability development and institutionalized cooperation amid a complex Indo-Pacific security environment.
In February 2026, Indonesian Defense Minister Sjafrie Sjamsoeddin and Japan Maritime Self-Defense Force Chief of Staff Adm. Akira Saito held talks in Jakarta to strengthen naval communication and coordination. They also discussed defense equipment cooperation, technology development, multilateral exercises and enhanced defense forums, signaling a shift toward structured operational planning.
“Located at the heart of the Indo-Pacific, the Indonesian Navy has long safeguarded vital sea lanes — benefiting not only Indonesia but the entire international community, including Japan, and contributing to a Free and Open Indo-Pacific,” Japan’s Defense Ministry stated.
Alex Jemadu, an international relations expert at Indonesia’s Pelita Harapan University, told FORUM that key areas “form the convergence of strategic interests between the two countries.” Those include safeguarding South China Sea trade routes under international law, ensuring defense cooperation protects extensive bilateral economic ties and supporting dialogue-based, conflict-resolution mechanisms.
The growing closeness between Jakarta and Tokyo “is driven by the convergence of maritime visions,” Budi Riyanto, an international relations lecturer at the London School of Public Relations in Indonesia, told FORUM. “Amid an increasingly difficult and uncertain security environment, both countries recognize that maritime stability is a fundamental prerequisite for regional prosperity,” he said.
Defense equipment cooperation is central to the partnership. In January 2026, Japan agreed to supply high-speed patrol boats to the Indonesian Navy under Tokyo’s Official Security Assistance framework. The grant program strengthens partners’ security and deterrence capabilities to support peace and stability.
Indonesian defense officials said the vessels will significantly bolster maritime security across the vast archipelago.
Riyanto also noted the nations’ plans for joint production of Japan’s Mogami-class frigates, which feature stealth designs and modular systems. The project would strengthen Indonesia’s maritime domain capabilities while building its domestic defense-industry capacity.
Such efforts are facilitated by a 2021 defense equipment and technology transfer agreement, according to Pudji Astuti, an analyst at Indonesia’s Defense Ministry. “Japan strongly supports the modernization of Indonesia’s maritime defense systems, particularly by enhancing Indonesia’s maritime capabilities through potential technology transfer of defense equipment, coastal radar technology and high-speed patrol vessels,” she told FORUM.
Jakarta and Tokyo also are broadening multilateral engagement. Japan’s Defense Ministry highlighted progress in unit-level exchanges, including joint exercises, and discussions on protecting military information to support deeper operational cooperation.
Riyanto highlighted the wider regional dimension. “By involving partners such as Australia and the United States, Indonesia and Japan strengthen an inclusive, but not exclusive, security architecture,” he said. “This creates stable maritime behavioral norms and prevents military miscalculations in disputed waters.”