India is moving to strengthen its navy with a new generation of submarines designed in Germany and to be built in India. The deal, worth around $8 billion (€7 billion), is expected to be signed this summer, according to the German Defense Minister Boris Pistorius.

The deal comes as the Indo‑Pacific turns into an increasingly contested arena, with submarines playing a central role. China's growing naval reach and Pakistan's deepening military ties with Beijing are sharpening India's sense of urgency.China's plan to dominate the seasTo view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video

The submarines in question are German-designed Type 214 boats, built by Thyssenkrupp Marine Systems, or TKMS. They are diesel-electric submarines, not nuclear-powered ones. But they include key technology that makes them especially valuable: air-independent propulsion (AIP).

That technology allows them to stay underwater much longer than other conventional submarines — making them harder to detect and better suited for patrols in crowded waters.

India's sea lanes are vital