BEIJING: Navies of China and Pakistan , holding nine-day exercises in the Arabian Sea to enhance their all-weather strategic partnership, have for the first-time deployed submarines, providing a rare major exposure to the Chinese navy in the region.The Arabian Sea region is strategically important for India as major ports including Kandla, Okha , Mumbai, Nhava Sheva (Navi Mumbai), Mormugão, New Mangalore, and Kochi are located there.The joint maritime exercises began on Monday in the North Arabian Sea, regarded strategically significant for China which is now developing Pakistan's deep water Gwadar port there.Gwadar is being connected through the over USD 60 billion China Pakistan Economic Corridor (CPEC) to China's Xinjiang province, providing a key land route to China to access the warm waters of Arabian Sea. India has objected to China over the CPEC as it is being laid through the Pakistan-occupied Kashmir (PoK).The Gwadar is also located close to Iran's Chabahar Port being jointly developed by Iran, India and Afghanistan to ensure a trade corridor for Indian exports to Afghanistan.The Arabian Sea provides entry to the Indian Ocean where China currently has built a logistics base at Djibouti in the Horn of Africa.The joint exercises are expected to be the first of many to come, as China and Pakistan have now developed a series of joint exercises covering the navy, army and air force, the PLA (People's Liberation Army) Daily, the official newspaper of the Chinese military, reported.The report said that this joint exercise is not related to ongoing regional affairs and is not aimed at any third party.The exercise is also the first between China and Pakistan that will feature anti-submarine and submarine rescue training, indicating a high-level of strategic mutual trust, state-run Global Times quoted experts as saying.