Image caption Low-income sub-Saharan countries have done well, says the IMF

Sub-Saharan Africa is expected to show 5% growth in 2011, according to the International Monetary Fund's latest regional report.

Its outlook for next year is even brighter, with 6% average growth.

However, the IMF's Africa director, Antoinette Sayeh, warned of the impact of global financial volatility on the region.

She told the BBC it could mean "lower exports, inward investment flows and decreasing aid levels".

Ms Sayeh also said that inflation, driven by high food and fuel prices, could become a problem.

She advised governments of the need to "tread a fine line between addressing the challenges posed by strong growth and preparing to ward off the potentially adverse effects of another global downturn".

Middle-income countries, most notably South Africa, have not had the same success, with growth of 3.5% this year.

The region has been hit by high unemployment and household debt, fragile consumer confidence and weak demand from Europe.