Defence Minister A K Antony on Wednesday inaugurated the annual joint naval fleet exercises codenamed "TROPEX 2012" in the Bay of Bengal and is spending a night on the country's lone aircraft carrier INS Viraat.

Earlier, he was received on arrival at INS Dega by the Flag Officer Commanding-in-Chief, Eastern Naval Command, Vice Admiral Anil Chopra, a naval release said.

Antony, accompanied by the Chief of Naval Staff Admiral Nirmal Verma, visited the indigenous stealth frigate INS Shivalik and is expected to supervise naval operations, including missile and rocket firings, air power demonstration and interceptor missions involving fighter aircraft of the Navy and the Air Force tomorrow during the two-day exercise.

Almost 40 ships including submarines and 13 naval aircraft and Unmanned Aerial Vehicles will participate in the demonstrations, the release said.

Units of the Indian Coast Guard and 18 aircraft of the Indian Air Force will also take part in the exercise. A variety of missile firings, Air Defence Exercises and anti-submarine drills will also be carried out, it added.

TROPEX is a major annual exercise of the combined fleets of the Navy conducted to test the force's preparedness to deal with any contingency.