'Act to end Africa food crisis'

Former UN head Kofi Annan recently called for a "green revolution" in Africa

Action is needed to prevent the current food crisis in Africa from becoming a disaster, the official heading a new UN food task force has warned.

Sir John Holmes told the BBC the solution to food shortages would be different for each country but there had to be a co-ordinated approach.

Escalating prices and shortages have sparked riots in more than half a dozen African states in recent months.

He said vulnerable children, pregnant woman and the old would be prioritised.

"We'll be trying to put together a comprehensive plan of action, but of course that needs to be translated into a local plan," he told the BBC's Network Africa programme.

The United Nations task force brings together the UN, the International Monetary Fund and the World Bank and other agencies.

Much of the focus appears to be on the need for some kind of "green revolution" among farmers - especially in Africa.

UN Secretary-General Ban Ki-moon recently said the world would need to find $1.7bn (£860m) to help them buy the seeds and fertilisers they needed.