Crisis talks are being held by G7 finance ministers in southern France.
The two-day meeting of the Group of Seven industrialised nations was called by France in an attempt to restore confidence in the world's financial markets.
There is mounting anxiety over Europe's debt crisis and the fragility of its banks.
The Organisation for Economic Co-operation and Development has predicted a further global slowdown this year.
The OECD suggested it is possible many major economies could go back into recession this year.
Before the G7 meeting began, International Monetary Fund managing director Christine Lagarde urged ''bold action''.
''The key message I wish to convey today is that countries must act now - and act boldly - to steer their economies through this dangerous new phase of the recovery,'' she said in London.
All this is happening at a time when the scope for policy action is considerably narrower than when the crisis first erupted.
But while the policy options may be fewer, there is a path to recovery, said Ms Lagarde.
No communique will be issued after the talks in Marseille, according to French Finance Minister Francois Baroin.
The OECD predicts the G7 economies will grow by 0.2% in the last three months of the year.
The agency also expects 0.3% growth in Britain in the fourth quarter, but said the economy could contract by as much as 1%.