Microsoft chairman Mr Bill Gates is to donate at least $1 billion to fund full college scholarships for minority students, by far his biggest charitable contribution to date.

The Gates Millennium Scholarships will cover room, board and tuition for at least 1,000 high school students a year over the next 20 years in the fields of education, mathematics, engineering and science. The Bill and Melinda Gates Foundation is worth $17 billion.

Students covered by the scholarships will be fully funded for their entire college education including any graduate work, according to the source, who asked not to be identified.