The Scots-born winner of the Nobel Prize for economics has issued a new warning about the dangers of handing out foreign aid to regimes such as Robert Mugabe.

Edinburgh-born Angus Deaton professor of economics and international affairs at Princeton University in the US said he was 'stunned' after discovering how much money had been given to Mugabe's government in Zimbabwe.

Professor Deaton, who celebrates his 70th birthday today, also admitted he cannot understand the fuss created by his prize, which was for his studies on the causes of poverty in the developing world.

The expert, whose views has drawn the ire of the United Nations and poverty activists such as billionaire Bill Gates and Bono, told a newspaper: "The issue is the unintended consequences. This idea of just giving people something helps perpetuate bad rule.

"Mugabe is still getting enormous amounts of money in foreign aid in Zimbabwe. I looked up the numbers recently and was stunned."

He added: "It's powerlessness that's the problem, not really the lack of money. If people are powerless, then giving them money isn't going to solve that problem."

The Royal Swedish Academy of Sciences, which awards the £630,000 prize, felt that Prof Deaton's work has transformed several fields of economics.

The organisation said: "To design economical policy that promotes welfare and reduces poverty, we must first understand individual consumption choices. More than anyone else, Angus Deaton has enhanced this understanding."

Prof Deaton is currently the Dwight D Eisenhower professor of economics and international affairs at the Woodrow Wilson School of Public and International Affairs at Princeton.

He was born in Edinburgh in 1945 to a Scottish mother an English father who rose from a Yorkshire coalminer to chief water engineer for the South of Scotland.

Prof Deaton also discussed his early years in Melrose in the interview.

He won a scholarship to Fettes private school, before earning his PhD at the University of Cambridge, where he later taught.

Despite spending his formative years among the country's wealthier classes, he maintained an aversion to aristocracy and privilege.

The Duke of Buccleuch owned all the land around Melrose and Prof Deaton recalled how local fisherman were denied full access to fishing lakes in the area.

He added: "It was a conspiracy between the church and the aristocracy -- who always seemed to me English. That was the big deal. The people with money didn't speak like us. It always seemed that there was an occupying power there."

Prof Deaton added that he viewed Scottish independence as "very dangerous" and paraphrased the author Ian McEwan. He said that with English and Scottish parents, a break in the Union would leave him feeling like he had been 'physically dismembered.'