NEW DELHI: India joined an elite club of nations this week with the launch of its own nuclear-powered submarine, but experts say it could be years before the prototype becomes a strategic asset.

INS Arihant (Destroyer of Enemies) began trials this week with its builders slating 2015 as the date for the commissioning of the 6,000-ton vessel with an 85-megawatt nuclear reactor.

The effort is a "disturbing factor" for Indian Ocean security, Admiral Noman Bashir, Pakistan's chief of naval staff, said in Beijing on Tuesday.