Sub-Saharan Africa's economies will expand at a slower rate in 2012 than earlier projected, undermined by global financial distress and a sluggish recovery in South Africa, the International Monetary Fund (IMF) said Monday.

Africa's growth has remained above 5% in the last eight years, underpinned by strong prices for its natural resources, better governance and growing disposable incomes.

In its latest Regional Economic Outlook, the IMF forecast 5.4% growth this year from 5.1% in 2011. Its previous projections were 5.9 and 5.5% respectively.

"The growth outlook for 2012 is somewhat less favourable than outlined in the October 2011 Regional Economic Outlook, with the growth projection for 2012 now cut by almost one-half a percentage point, driven in large part by the weaker economic outlook for South Africa," the IMF said.

Growth in Africa's economic powerhouse was likely to be a relatively modest 2.7% this year and 3.4% in the next, held back by its reliance on trade with Europe and close links with western financial markets, the Fund said.

However, an upturn in drought-hit east Africa, fresh output in new natural resource producers such as Niger and Sierra Leone and recovery in post-conflict nations such as Ivory Coast should help boost the continent's economic activity in 2012.

Sierra Leone and Niger could post outstanding growth of 35.9 and 14% respectively. Big oil-producers Nigeria and Angola will also be major drivers of the expansion.

Economies reliant on non-renewable resources are experiencing faster growth but are also suffering the worst volatility in exports, revenues and GDP expansion, the IMF said.