New Delhi: In a major step toward enhancing India's maritime defense capabilities, the Indian Navy is set to acquire three new state-of-the-art submarines under a massive ₹38,000 crore deal with Mazagon Dock Shipbuilders Limited (MDL), a premier public sector defense shipyard. The agreement, expected to be finalized this month, represents one of the country’s largest indigenous defense contracts in recent years.

The submarines will be constructed under the ambit of the Atmanirbhar Bharat (Self-Reliant India) initiative, which aims to reduce dependence on foreign military imports and promote domestic defense manufacturing. These vessels will be part of the Kalvari-class, a proven line of diesel-electric attack submarines developed through a strategic partnership between India and France’s Naval Group.

Around 60% of the components used in these submarines will be sourced or manufactured within India, ensuring significant technology transfer and bolstering the local defense industry.

One of the standout features of these new submarines is the integration of the indigenously developed Air Independent Propulsion (AIP) system, designed by India’s Defence Research and Development Organisation (DRDO). Unlike traditional diesel-electric submarines, which must frequently surface to recharge their batteries and take in oxygen, submarines equipped with the AIP system can remain submerged for up to 21 days, dramatically increasing their stealth and operational range.

This development marks a significant leap in India's underwater warfare capability, as none of the Navy’s current conventional submarines possess this long-endurance underwater capability.

The Kalvari-class submarines are a customized version of the French Scorpène-class platform, fine-tuned to meet the operational demands of the Indian Navy. These submarines are equipped to launch long-range heavyweight torpedoes and anti-ship missiles, and are also used for intelligence gathering, surveillance, and reconnaissance missions.

At present, the Indian Navy operates five Kalvari-class submarines. The most recent addition, INS Vagsheer, was commissioned in January 2025. The inclusion of three more vessels will bring the total strength of the Kalvari fleet to nine, significantly boosting underwater deterrence and strategic depth.

This new procurement is part of a broader effort to modernize the Navy's submarine force, which currently relies heavily on aging Soviet-era Kilo-class submarines. These older vessels, though reliable, are increasingly outmatched by modern threats and technologies. The new Kalvari-class submarines, with their enhanced endurance and advanced systems, are expected to gradually replace the Kilo-class, marking a transition to a more advanced and indigenously-supported underwater fleet.

This submarine deal is not just a milestone in India’s defense manufacturing journey, but also a strategic move to counterbalance growing maritime challenges in the Indo-Pacific region. The extended underwater endurance, increased stealth, and technological superiority of the upcoming submarines will provide India with a critical edge in securing its interests across contested sea lanes and in deterring potential adversaries.

Once the deal is inked, construction is expected to commence swiftly at MDL’s Mumbai shipyard, with delivery timelines likely to be spread over the next five to seven years.