The famine that is threatening to devastate southern Africa has frightening similarities to the one in Ethiopia and the Sudan that prompted the LiveAid concert, Bob Geldof has said.

The former frontman of the Boomtown Rats told BBC Radio 4's Today programme that domestic politics had much to do with the plight of people in southern Africa but that developed countries still had to rally round to try to help when a crisis occurred.

Mugabe is a murderous thug but we can't predict that this man is going to go completely mad and devastate his own homeland

Bob Geldof

He was particularly critical of Zimbabwe's leader Robert Mugabe whom Mr Geldof described as a "murderous thug".

But he insisted that ultimately the problems faced in southern Africa were supranational and should be sorted out with the help of the West.

Supranational

"It's not an insurmountable problem in the scale of things and given that 17 years have passed since LiveAid... one would have thought that peopple would've understood that it's a supranational problem.

"One country cannot deal with it."

He said that the problem of famine would not cost very much to solve and that although he said people got "bored stupid" with seeing images of starving people he saw no other alternative.

Asked about particular problems in Zimbabwe Mr Geldof said: "Mugabe is a murderous thug but we can't predict that this man is going to go completely mad and devastate his own homeland and cling to power at any cost albeit that it may cost the lives of millions of his countrymen.

"We can't predict these emergencies - by definition they are emergencies."