India is about to take another big step forward in its nuclear weapons delivery capacity with plans to flight-test the Agni-V ballistic missile this year.

The Agni-V would represent a big step forward in India's strategic weapons arsenal given its range in excess of 5,000 km (3,100 mi.). Once testing begins, developers hope to declare the Agni-V operational in two years. The missile's predecessor, the 3,500-km-range Agni-III, is currently under induction into strategic missile groups governed by India's nuclear command.

The development comes as the Stockholm International Peace Research Institute warns that India and Pakistan “continue to develop new ballistic and cruise missile systems capable of delivering nuclear weapons. They are also expanding their capacities to produce fissile material for military purposes.” The organization notes in its latest yearbook that the Indian nuclear stockpile is estimated to have grown to 80-110 warheads, up from 60-80 a year ago, with Pakistan's inventory at 90-110 warheads, up from 70-90.

Earlier this month, in a departure from the Indian government's traditional reluctance to talk publicly about the country's strategic weapons arsenal, Indian Defense Minister A.K. Antony ordered the country's missile program administrators to speed up the Agni-V program, saying, “the [Defense Research Development Organization] must demonstrate its capability to reach the range of 5,000 km at the earliest.” DRDO chief Vijay Saraswat adds that the 22-meter-long (72-ft.) Agni-V would be test-fired in December.

In May, the Indian Nuclear Command Authority (NCA) reviewed progress on the indigenous submarine-launched ballistic missile (SSBN) program and the country's long-range missiles. That meeting appears to have led to the decision to speed up the Agni-V program and ensure that there were no slippages in the induction of India's first nuclear-powered ballistic missile submarine, the Arihant, next year.

The Agni-V's range puts China—India's principal focus as far as nuclear deterrence is concerned—fully within range of a retaliatory strike. India functions on a no-first-strike nuclear policy. The Agni-V will be cannisterized, road-mobile and designed for quick deployment. It was revealed last February that the Agni-V is also being developed to carry multiple independently targetable re-entry vehicle (MIRV) warhead payloads.

An Agni-V program developer says “the missile will soon be ready in all respects for its first test. We are continuing with subsystem testing and simulation trials. We do not foresee any delays.” The 700-km-range Agni-I and 2,000-km-range Agni-II are already operational.

The three-stage prototype Agni-V that will be fired is currently under integration and fabrication. The DRDO's Advanced Systems Laboratory (ASL) has tested the missile's three stages separately on the ground. The Agni-V will be India's first strategic missile with a rocket motor built from composites, unlike the metal construction used in all earlier Agni-series missiles. Over the next few months, confirmatory ground evaluations of all major subsystems will be completed. Last year, the program team grappled with delays arising from changes to the weapon's payload structure, the addition of extra heat shields and alterations to the missile's re-entry mechanism.

In terms of range, the Indian government does not feel the need to go beyond what the Agni-V is capable of, making it perhaps the last long-range ballistic missile in the country's guided weapons program for the foreseeable future. The DRDO has revealed that while it has no official sanction to build an intercontinental ballistic missile (ICBM) with ranges in excess of 8,000 km, it has developed the critical technology to build one quickly if necessary.

Less is known about India's K-series of submarine-launched missiles. While the K-15, with a range of 750 km, continues to be tested to meet the specifications of India's first indigenous SSBN, the Arihant, DRDO engineers have unofficially spoken of a long-range missile being developed for underwater launch. While the Agni-V will fulfill the land leg of India's nuclear deterrent, it is the 3,500-km-range K-4 missile that will truly complete the country's strategic triad, providing it with a crucial strike capability from the sea. India's Arihant-class SSBNs, the first of which is scheduled to enter service late next year, are being built to deploy four K-4s and 12 K-15s. An even longer-range variant of the K-4, with a range of 5,000 km, is also being planned.