"Exchange control is something of the past," said Kirubi, who is chairman of Kenya's Haco Industries, a group with interests in property management, communication, media and investments.

Kirubi said Kenya liberalised its currency controls many years ago, and today had "one of the strongest currencies", even during the recent election unrest.

Instead of ministers going to Washington to seek funds for development, they were able to raise capital locally. "If you liberalise people will feel free to bring money to this country and not plan how to take their money out because they are not allowed to," he told Sapa afterwards.

"People must be free to move and to bring in their wealth. Controls do not work. What they do is drive revenues from the countries to outside safe havens."

Kirubi said he had been talking to Manuel on the issue for the last ten years.

"He laughs about it, but I'm sure he does hear what I say," he said.

"When I come here, I come with my dollars, and to change money is like buying a whole building. I have to produce my passport, I have to do all sorts of things.

"This is not the way you manage modern economies."

Manuel, responding to Kirubi in the discussion, said there were 13 countries in the world that had grown at seven percent or more for 25 years or longer, and none of them were "raging free marketeers". "Chris, most of them have had exchange controls," he said.

Kirubi drew laughter from the audience when he said people who spoke to him wanted to know how Kenya was doing in the wake of the poll violence.

"Kenya is fine," he said.

"After the chaos we found a way of dealing with it. We exported it."

Manuel, sitting alongside him, smiled wryly.

South Africa was recently hit by a wave of xenophobic violence that left 59 people dead.