Representatives from the navies of 45 nations, including the United States, Britain and Japan, are participating in the exercise titled "Aman" or peace, which began Friday in the Northern Arabian sea.
Pakistan's navy says several countries also sent vessels in addition to sailors to participate in the exercise. Pakistan has been hosting the exercise since 2007 but has never invited archrival neighboring India.
Pakistan and India have a history of bitter relations. They have fought two of their three wars over disputed the Himalayan region of Kashmir since their independence from British rule in 1947