The NITI Aayog has prepared a plan for economic transformation of Mumbai, Surat, Varanasi and Vizag and help India become a developed economy by 2047, its CEO BVR Subrahmanyam said on Saturday. He also said the Aayog plans to prepare economic planning of 20-25 more cities, as they are the centre of economic activities. A vision document is being prepared by NITI Aayog for India to become a developed economy of USD 30 trillion by 2047, and it will be released by Prime Minister Narendra Modi. "We used to only prepare urban planning of cities, not economic planning..NITI Aayog has prepared economic planning of Mumbai, Surat, Varanasi and Vizag, for economic transformation of these cities," he said at an event here.