The International Monetary Fund (IMF ) has downgraded its forecast for global economic .

It now expects economic activity to increase 3.4% this year followed by 3.6% in 2017.

 

That means growth of 0.2% less each year than when the agency last published a forecast in October.

And there are warnings about the risks. The report says that if key challenges are not successfully managed, "global growth could be derailed".

In many respects, the picture is a familiar one. The recovery after the financial crisis continues. But in the rich countries, it is still "modest and uneven". 

Only three large advanced economies are forecast to beat 2% growth this year: the US, the UK and one of the eurozone's crisis-hit nations, Spain, which has had its forecast upgraded.

The forecast for the UK is unchanged, at 2.2% for both years. 

The report describes the picture for many emerging and developing economies as "challenging".

The largest downgrade for any individual economy is Brazil, where the IMF now predicts a contraction of 3.5% this year and no growth at all in 2017. That reflects the political uncertainty arising from the investigation into corruption at the oil company Petrobras.

Russia, hit by the decline in prices of its oil exports, is also likely to remain in recession this year before returning to modest growth next year.