Speaking at the launch at the World Economics Forum in Davos, Switzerland, Gates committed to tripling his own foundation's funding against tuberculosis from 300 million dollars to a total of 900 million dollars by 2015.

"This is a very tough disease," Gates told a press conference, underscoring the importance and global ambition of the new program.

"I'm very excited to see it being created and I want to do everything I can to back it," he added.

Nigerian President Olusegun Obasanjo, British Chancellor of the Exchequer Gordon Brown and Gates urged business and political leaders gathered here to back the new program.

Brown said it was now time to deliver after global leaders pledged last year to help Africa fight chronic under-development and disease.

Obasanjo picked up on the theme, saying: "With little words of promises and pledges Bill has shown the way, that this is the year of delivery."

But, he added with a smile, "In my part of the world we always like things that are round. Why do you have to go short of one billion dollars? Its easy to pronounce."

Looking ahead, Brown said: "I believe that the issue is going to move from the support of individual programs such as we are doing today to building the capacity of health care systems in the countries that we are talking about."