Forbes richlist: Gap tightens between world's wealthiest
7 March 2012 Last updated at 19:17 GMT
Mexican tycoon Carlos Slim has once again come top of Forbes magazine's annual list of the world's richest billionaires - but the gap between the world's wealthiest is tightening.
The magazine estimates that Mr Slim, whose business interests range from telecommunications to construction, is worth $69bn (£44bn).
He is followed by Microsoft founder Bill Gates on $61bn, and US investor Warren Buffett on $44bn.
Steve Forbes, chairman and editor in chief of Forbes Media, spoke to the BBC's World Business Report from New York.