Russia has agreed to lease out a second nuclear attack submarine of the Akula class to India this month in a deal worth around $2 billion. The lease of the first Akula-class submarine that the Indian Navy calls INS Chakra expires in 2021. The lease deal for the second nuclear submarine was finalised at a summit-level meeting between Russian President Vladimir Putin and Prime Minister Narendra Modi.

• The attack submarine will arrive in Indian waters in 2020-21. The decision to acquire a second Russian nuclear submarine on lease was taken after India’s first indigenously built nuclear submarine INS Arihant was quietly commissioned days before the September 18 Uri terrorist attack.
• The 6,000-tonne indigenous nuclear submarine that can fire nuclear ballistic missiles up to a range of 3,500- km was commissioned in secret even as Pakistan Defence Minister Khwaja Asif was invoking in public the possibility of using tactical nuclear weapons against India.
• The Akula-class submarine is nuclear powered but is armed with conventional land attack missiles. The Arihant, however, is part of India’s nuclear triad with Agni V missiles and aircraft-delivered nukes making up the other two legs. Given the sharp variation of temperatures with depth in Indian waters, the difficulty of detecting the Arihant makes it a potent weapon.
• It is understood that Arihant has already been operationally deployed. The second indigenous nuclear submarine of the same class, INS Aridhaman, will slip into the water in 2018.
• Powered by an 83 MW miniaturized reactor which went critical on August 10, 2013, the Arihant had to undergo extensive diving and missile firing trials.