Sonia, Manmohan in top 20 of Forbes' most powerful list

Rounding out the Top 10 are US Federal Reserve Chairman Ben S. Bernanke (No. 6), Saudi Arabian King Abdullah bin Abdulaziz al Saud (No. 7), European Central Bank President Mario Draghi (No. 8), General Secretary, Communist Party of China Xi Jinping (No. 9) and British Prime Minister David Cameron (No. 10).

Facebook CEO Mark Zuckerberg (No. 25) dropped out of the Top 10 to 25, from No. 9 in 2011.

Pakistan Army chief General Ashfaq Parvez Kayani is listed 28th on the list, while Zaheer ul-Islam the "new head of Pakistan's notorious intelligence service" Inter-Services Intelligence is ranked 52nd.

Among the 14 newcomers to the list are LinkedIn co-founder Reid Hoffman (No. 71), the world's most powerful venture capitalist and SpaceX CEO Elon Musk (No. 66), the entrepreneur behind Paypal, Tesla Motors and the private space industry.