Olivier Blanchard, the chief economist at the International Monetary Fund (IMF) said in his foreword to the latest World Economic Outlook report that crisis-hit advanced economies were facing a "continuing, but weak and bumpy, expansion".

He said that compared with the last outlook report, issued in April, global economic recovery "has become much more uncertain". The world economy suffers from the confluence of two adverse developments, according to Blanchard. The first was a much slower