NEW DELHI: In a rare, official comment on the Indian nuclear attack submarine project, a top Naval officer has said that work has started on a new class of vessels after a government go ahead two months ago and the target is to shorten the developmental time to under 15 years.While India has traditionally shied from commenting on its nuclear fleet - for years the existence of the Arihant nuclear missile submarine was denied despite a large Indo-Russian team working on the project - the Navy has said that it is confident of executing the order with a brand new design."The government has given approvals for six new SSNs ( nuclear attack submarines ) earlier this year. We have started work but still are at the pen to paper stage," Vice Admiral P Murugesan , the Vice Chief of Naval staff said in response to a question by ET.The top officer expressed confidence in the abilities of the navy's submarine design bureau to come out with a new class of vessels in less than 15 years. "These things take time but we will be able to improve on the timelines that the pioneers (nations) have set which typically took over 15 years for such a project," the Vice Chief said.The senior officer shared that the aspiration of the Navy - which currently has 48 ships under construction on various shipyards across the nation - is to become a 200 ship navy by 2027. At present, the Navy operates 137 combatants with new ships being added at a rate of 4-5 a year.As reported by ET, to boost its underwater capabilities, the Navy is planning to build at least six SSNs in India, with financial sanction given in February for the project that could cost upwards of Rs 90,000 crore. To be fitted with the indigenous vertically launched Brahmos missile, the vessels are to be built at the Vizag-based ship building centre with the involvement of L&T.India is also in final talks with Russia to lease a new nuclear attack submarine with sources telling ET that the Navy is looking for a newly built, customised submarine under the Chakra 3 project. The only nuclear attack submarine of this kind being produced in Russia currently is the Yasen class, the least detectable submarine it has ever built.