India bolsters naval deterrence with new SSBN patrols and four domestically built warships

India’s nuclear‑powered ballistic missile submarine (SSBN) fleet now operates three boats—INS Arihant, INS Arighat and INS Aridhaman—with a fourth, INS Arisudan, slated for 2027. The expansion enables a continuous at‑sea deterrence (CASD) posture, allowing at least one SSBN to patrol year‑round, supported by a new jetty at Mauritius’ Agalega Island and a limited number of nuclear warheads aboard the submarines.

In parallel, the Indian Navy has commissioned four locally built vessels. Project 17A stealth frigates INS Dunagiri and INS Mahendragiri enhance surface combat and anti‑ship capabilities. The Sandhayak‑class survey ship INS Sanshodhak provides seabed mapping for navigation and disaster response, while the Arnala‑class anti‑submarine craft INS Agray strengthens coastal submarine hunting. Together, these additions expand India’s combat reach, maritime domain awareness and coastal defence.

The combined developments signal a shift toward a more layered and persistent maritime security strategy, affecting the regional deterrence balance, particularly with Pakistan.