After taking off in the frontline Sukhoi-30 MKI, President Pratibha Patil on Monday once again donned military fatigues to ride a T-90 main battle tank, becoming the first head of the State to do so.

Dressed in black overalls worn by the personnel of the tank regiments, the 76-year-old President entered the exercise 'Sudarshan Shakti' here riding in the main battle tank with army chief general V K Singh.

Defence minister A K Antony also arrived in a tank to witness the massive exercise and was accompanied by southern army commander Lt Gen A K Singh.

This is her second ride in a military vehicle as she flew the Sukhoi-30MKI fighter aircraft at the Lohegaon air base in Pune in 2009.

The President along with the defence minister will review the ongoing exercise in the deserts of Rajasthan involving over 50,000 troops, 300 tanks and 250 artillery guns.

The exercise also involves operation by aircraft such as Su-30 MKI, Jaguars, Mig-27 and Mig-21 AWACS and helicopters.

It will also put to test the newly-inducted communication and battlefield surveillance radars by integrating them with all the war fighting assets of the army and the IAF.

The exercise will help the southern command to validate its war-fighting concepts while working towards 'capability- based approach' relying on a series of transformational initiatives, concepts, organisational structures and absorption of new age technologies.