Asia Defense | Security | East Asia | South Asia

India and Japan’s Emerging Shipbuilding Partnership 

The future of India-Japan security cooperation lies in shipyards – and maybe with the Mogami-class frigate.

Indian Prime Minister Narendra Modi welcomes Japanese Prime Minister Takaichi Sane to Hyderabad House, New Delhi, India, July 2, 2026.

The India-Japan defense partnership is entering a new phase. The two countries have deepened maritime cooperation for over a decade through regular naval exercises, defense dialogues, logistics agreements, and shared support for a Free and Open Indo-Pacific. Now the strategic demands of an increasingly contested maritime environment require the partnership to evolve beyond operational cooperation. Recent developments such as the transfer of Japan’s advanced Unified Complex Radio Antenna (UNICORN) mast technology to the Indian Navy, Japan’s relaxation of its arms exports policy, and discussions on co-developing Mogami-class frigates suggest that the future of India-Japan security cooperation also lies in the shipyards.

This shift reflects broader changes in the Indo-Pacific security landscape. China’s expansionist behavior and its increasing presence in the Indian Ocean have prompted like-minded countries to strengthen both deterrence and defense-industrial resilience. For both India and Japan, the challenge is now about building the industrial capacity needed to sustain long-term maritime power. Defense industrial cooperation, particularly in naval shipbuilding, provides a pathway to achieve that objective.

The agreement on Japan’s UNICORN mast system signed in November 2024 marks an important milestone in this regard. UNICORN is designed to integrate multiple communication, radar, and electronic warfare functions into a single mast to significantly improve warships’ operational efficiency while also reducing their radar signature. Importantly, the agreement showcases Japan’s growing confidence in transferring sophisticated defense technology to India as it signals an unprecedented level of strategic trust between the two nations. 

The UNICORN agreement serves as proof that India and Japan can move beyond a conventional buyer-seller relationship toward more collaborative defense production. The logical next step here is shipbuilding. India is a trusted strategic partner for Japan with an expanding defense industrial base capable of supporting larger collaborative projects. For India, which seeks to modernize its naval capabilities while advancing the objectives of Aatmanirbhar Bharat (self-reliance), access to Japanese technologies can complement indigenous shipbuilding programs. 

During Japanese Prime Minister Takaichi Sanae’s recent visit to India in July 2026 for the 16th India-Japan annual summit, the growing convergence between defense industrial cooperation and economic security was underscored. The summit emphasized enhancing defense industrial cooperation between the two countries. Both governments recognized that resilient supply chains, trusted technologies, and defense manufacturing are integral to national security. 

Shipbuilding sits at the intersection of these priorities. Joint shipbuilding creates long-term industrial linkages that involve advanced manufacturing, electronics, propulsion systems, artificial intelligence, and maintenance ecosystems. Such cooperation also strengthens both military capability and economic resilience. In this context, Japan’s proposal to jointly develop and produce Mogami-class frigates with India deserves serious consideration. The Mogami class represents one of the most advanced multi-mission frigates currently in production, combining stealth features, high levels of automation, anti-submarine warfare capabilities, and modular mission flexibility. 

For India, collaboration on such a platform may go well beyond acquiring another class of warship. Indian shipyards have progressed in he design and construction of destroyers, frigates, and offshore patrol vessels. However, Japan’s expertise in automation,........

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