NEW DELHI — Western competitors could face stiffer competition from the Russians in India’s forthcoming US $12 billion tender for the purchase of six conventional submarines. The Indian Defence Ministry is requiring that submarines in the competition be capable of mounting the Indo-Russian BrahMos cruise missile.

India’s Defence Research and Development Organisation, which is jointly producing the BrahMos with Russia, has persuaded the MoD to incorporate the requirement for the tender, expected to be floated by the end of the year.

DCNS of France, Navantia of Spain and HDW of Germany will offer their submarines in the competition. The Russians, meanwhile, told the Indian Navy this month that their Amur-class submarines could accommodate the BrahMos missile with little modification.

No executive from DCNS, Navantia or HDW would comment on their boats’ ability to carry the missile.

India is finalizing a formal tender to purchase six advanced conventional submarines with air-independent propulsion technology.

The six submarines are to be purchased within the limitations of the Missile Technology Control Regime, which restricts the proliferation of missiles capable of flying beyond 300 kilometers, an MoD official said.

BahMos is homemade and has a range of less than 300 kilometers, which would be best suited for the submarine, the MoD source said.

The submarines are to have a surface speed of 12 knots and submerged speed of 19 knots. They will have a range of 50 to 60 days of navigation on the surface and 20 to 30 days of navigation submerged at 4 knots.

Two of the six submarines are to be made in the overseas shipyard and the remaining four are slotted to be license-produced only in a state-owned shipyard.

The major fire on the Russian-made Sindhurakshak last month has dropped the operational strength of the Indian Navy submarines to only 11. With the decommissioning of the aging German HDW-class submarines next year, the Indian Navy’s total submarine strength could fall to as low as seven by 2015. The fact that the Indian Navy’s submarine fleet size has dropped so low is a point of major concern in the ranks, especially since China’s sub fleet is more than 60, an official said.