The much-awaited Akula-II class Nerpa attack submarine from Russia will not meet its year-end schedule of delivery to the India’s navy, according to Indian naval sources.

The 110m-long, 8,140t submarine is to be leased by Russia for ten years under a $650m contract signed in January 2004.

The navy has refused to accept the submarine from its Russian counterparts due to inadequate training of its teams to operate the vessel.

Indian naval teams will undergo training for five more months, which means the submarine will be delivered in March 2011, according to The Tribune.

The Nerpa was initially slated for lease to India in mid-2008, which was rescheduled for June 2010 after a $65m re-fit.

The Indo-Russian group on military technical cooperation, which met in July this year, promised the submarine would be delivered by the end of 2010.

The Nerpa will bridge the operational gap between now and the commissioning of the indigenously built nuclear-sub, the INS Arihant, which will join the fleet in 2012.