Boosting growth is a vital part of raising living standards in Africa

According to the UN Economic Commission for Africa, the continent's economies will grow by 5.8% on average in 2007, up from 5.7% a year earlier.

Better management and demand for commodities will boost expansion.

However, to keep growing, Africa needs to diversify its economic output and spend on infrastructure, the UN warned.

Active policies

"African economies continue to sustain what we call the good momentum of the past few years," said Eloho Otobo of the UN's Commission for Africa.

FASTEST GROWING Mauritania 19.8% Angola 17.6% Mozambique 7.9%

"The growth momentum, however, rests on a very, very fragile foundation."

A number of factors pose risks to growth in Africa, including the spread of HIV/Aids that threatens to incapacitate a large chunk of the workforce, the UN said in its report, called Accelerating Africa's Development through Diversification.

At the same time, African nations need to make themselves less reliant on key industries, open up borders to trade and look to diversify output and production to insulate themselves against an external shock or downturn in the market.

WORST PERFORMERS Zimbabwe -4.4% Seychelles 1% Swaziland 1.2% Comoros 1.2% Ivory Coast 1.2%

Nations also need to invest more in infrastructure projects to ensure a steady supply of energy, as well as better regional power and transport networks, the UN added.

"The time has come for Africa to embark on a more systematic effort at diversifying its economy," Mr Otobo said.

"This can only come about by promoting proactive growth policies."

League table

The best-performing economy in Africa last year was Mauritania, which grew by 19.8% as it benefited from oil revenues, the UN said.

Political instability is not helping Zimbabwe's economic performance

Angola was the second-best, expanding by 17.6%, and Mozambique was in third position, posting growth of 7.9%.

Zimbabwe was the worst performer. Its economy contracted by 4.4% in 2006 because of "political difficulties exacerbated by recurrent droughts", the UN said in its report.

The other nations in the bottom five were the Comoros, Ivory Coast, the Seychelles and Swaziland.