Pakistan has mobilised about 50,000 troops and air force elements for its biggest ever Armyexercise that will begin tomorrow along the eastern border with India.Military officials said in Islamabad the exercise, code named Azm-e-Nau 3 (New Resolve) is aimed at training troops for the threat of a conventional war with India.The wargame, to continue till May 13, will be the largest manoeuvres conducted by the Pakistan Army since the Zarb-e-Momin exercise in 1989.The Pakistan Army has traditionally perceived India as its main threat though security experts, including those from the US, have said the force now needs to focus on tackling the Taliban and other militant groups active along the western border with Afghanistan.