The UK has pledged a further $15bn to the IMF, after Christine Lagarde revealed that member states had promised a total of $456bn for its new crisis fund.
China will contribute $43bn, state news agency Xinhua confirmed on Tuesday morning.
They held back two months ago when the IMF solicited commitments at its spring meetings in Washington and only gathered a firm $340bn.
That was well below the $500bn the Fund’s own economists had said would be an adequate expansion of its crisis intervention funding, given the potential of more contagion in the troubled eurozone.
The largest economy, the US, is not contributing, despite its huge voting power on the IMF board.
While Washington has insisted Europe has enough resources to resolve its problems itself, it is also clear that the deeply divided Congress is in no mood, given the US economic problems, to contribute rescue funds for others.