NEW DELHI: India can develop a nuclear-capable missile with a strike range of 10,000-km, rivalling China's DF-31A missile that can hit targets 11,200-km away, but does not see the operational need for it given "the existing threat perceptions".

All gung-ho a day after the second test of the 5,000-km Agni-V, the country's first inter-continental ballistic missile (ICBM), DRDO chief Avinash Chander on Monday asserted it would take just about "two-and-a-half years'' to develop a 10,000-km missile if required.

"Range is the least problematic area. We have the full capability to go to any range...it's just a question of additional propellant and larger motors. But, as of now, we don't see the need for a higher range,'' he said.

Agni-V brings the whole of China -- including its northernmost city of Habin - and Asia as well as parts of Europe, Africa and Australia within its strike envelope.

"I don't see why we should be diffident about our capabilities. Agni-V is definitely an ICBM,'' said Chander. Largely the preserve of the Big-5 countries, the US, Russia, China, France and UK, an ICBM usually signifies a missile over 5,500 km.

Agni-V will now be tested early next year in a "canister-launch version'' to give armed forces the requisite operational flexibility in swiftly transporting and firing it from atop a launcher truck. "It will reduce the reaction time drastically...just a few minutes from 'stop-to-launch'. Agni-V will be inducted within two years after three-four more tests. All future strategic missiles will be canisterised,'' said Chander.

Though the armed forces have Agni-I (700-km), Agni-II (2,000-km) and Agni-III (3,000-km), and are on course to induct Agni-IV (3,500-km) and Agni-V by 2015-2016, the lack of a long-range submarine-launched ballistic missile (SLBM) remains a big gap in their nuclear deterrence capabilities.

Chander, himself a missile scientist, did say the 750-km K-15 SLBM would be tested from India's first nuclear submarine INS Arihant, which will soon head for sea trials'' after its miniature atomic reactor went critical'' last month, towards end-2013 or early-2014.

"K-15 is fully ready for integration with the submarine,'' he said. Though there is a 3,500-km K-4 missile in the works, the K-15 dwarfs in comparison to the over 5,000-km SLBMs wielded by the Big-5 nations. Quizzed about this, the DRDO chief said, "It's too early to talk of an SLBM which is also an ICBM.''

But DRDO is actively working on manoeuvering warheads or intelligent re-entry vehicles'' to defeat enemy ballistic missile defence systems as well as MIRVs (multiple independently targetable re-entry vehicles) for the Agni series of missiles.

Agni-V may be a "single warhead missile'' but Agni-VI and its successors will have MIRV payloads - a single missile carrying several nuclear warheads, each programmed to hit different targets - as well as longer ranges.