Prime Minister Gordon Brown is deemed to be the 29th most powerful person in a world, according to a list of 67 which fails to include the Queen.
The PM is joined by BBC director-general Mark Thompson, who at number 65 is the only other Briton to feature in the index compiled by business magazine Forbes.
US President Barack Obama tops the inaugural World's Most Powerful People list, followed by his Chinese counterpart Hu Jintao.
Terrorist mastermind Osama bin Laden comes in at number 37 on the index.
Forbes narrowed the list down to 67 people, a number based on the belief that you can reduce the world's 6.7 billion people to the one in every 100 million that matter.
Compilers used four criteria: the number of people influenced, the ability to project power beyond your sphere of influence, control of financial resources and how actively the subject wields power.
Messrs Obama and Hu are joined by Russian prime minister and former president Vladimir Putin in the top three.
Federal Reserve chairman Ben Bernanke is the highest ranking non-politician, placed fourth in the index.
Other notables include News Corp chairman Rupert Murdoch at number seven and Microsoft founder Bill Gates, placed 10th.
French president Nicolas Sarkozy comes in at 56th, some 11 slots below chat show queen Oprah Winfrey.
