Olympic stars to support hunger summit
12 August 2012 Last updated at 12:07 BST
Olympic stars have backed a campaign against child malnutrition in poor countries.
The athletes have written an open letter to David Cameron ahead of a "hunger summit" at Downing Street.
They urged the prime minister to make the issue the top priority for the UK's presidency of the G8 next year.
Mr Cameron said he was determined that the UK would help to tackle child malnutrition around the world.
Mike Wooldridge reports.