New Delhi, Dec. 25 -- As part of a broader effort to cut costs, Bharat Sanchar Nigam Ltd (BSNL) will shut down its 3G mobile services nationwide. The state-owned telecom operator also plans to terminate annual maintenance contracts (AMCs) with vendors such as Nokia and Chinese equipment maker ZTE for the 3G sites, according to two officials familiar with the matter and letters seen by Mint. The move comes as the state-run telecom operator focuses on its 4G network, having currently installed 97,481 4G towers across the country. "Keeping in view the above progress on 4G Network, circle heads are hereby authorized to shut down the 3G services wherever feasible in their areas," the telecom operator said in a letter on 10 December to chief gene...