The Group of 20 rich and developing nations asked the IMF to propose ways that it could help stop countries under severe market pressure from toppling into a full-blown crisis with potential global repercussions.
The move appeared aimed at Italy and Spain, the eurozone's third and fourth largest economies, which have seen their funding costs spike amid growing worries over the currency union's stability. The rest of Europe cannot afford to bail out Spain or Italy should they run out of money.
Until now, the IMF has funded about a third of the bailouts of Greece, Ireland and Portugal, but helping the eurozone to stem contagion beyond those countries would require a broader use of resources that would go far beyond the fund's traditional role of providing rescue loans to cash-strapped governments.
But while acknowledging that the IMF has a role to play in containing the continent's debt problems, G-20 ministers made clear Saturday that Europe must first come up with its own solutions.
"Of course, even though the world has a big stake in Europe doing this effectively, Europe itself has the strongest interest," U.S. Treasury Secretary Timothy Geithner told reporters after a two-day meeting of G-20 finance ministers and central bank governors in Paris.
"I think they've come to recognize that, if you underdo it, it's going to be more expensive."
Eurozone ministers sketched out a plan to their counterparts on Saturday and have promised that it will restore confidence in Europe and its banks when they unveil it next weekend.
At their Oct. 23 summit in Brussels, European leaders are expected to sign off on a scheme to maximize the impact of their euro440 billion ($600 billion) bailout fund, a plan to recapitalize banks across the continent to ensure they can withstand worsening market turmoil, and a second bailout for Greece.
Part of an effort to shore up shaky countries on the continent may include a bigger role for the IMF, too.
"What has been asked of us is instruments that are more flexible, more short term, that allow countries in good economic health but in difficulty to resist," the IMF's managing director Christine Lagarde said.
She said G-20 leaders would consider the new tools at their summit in Cannes, France, early next month.
The IMF's investigation of new instruments reflects the extent to which the eurozone's debt crisis has affected the rest of the global economy.
"We heard loud and clear that the emerging markets in particular were very concerned about the risk of contagion from advanced economies to emerging markets and to low-income countries," Lagarde said.
The G-20 also committed to making sure that the IMF has the resources it needs to stabilize the world economy, indicating that an increase in its funding was possible. But there is resistance to such a move.
Geithner, for instance, stressed that the IMF, with $390 billion on hand, didn't need any more funding, although he said the IMF should continue to play its important role in containing the turmoil.
"That is a very, very substantial amount of financial firepower," he said. After Europe unveils its plan, "if there's a case for more use of the IMF's existing resources, we'd be supportive of that."
In discussing the requested list of tools, Lagarde said the IMF's efforts would focus on "short-term liquidity instruments available to what we call the 'non-consenting' victims of the economic crisis."
She gave the example of precautionary credit lines the IMF offered to several countries after the collapse of U.S. investment bank Lehman Brothers in 2008, and said the new tools could go in a similar direction.
Precautionary credit lines are linked to fewer conditions than traditional IMF rescue loans that come only in return for radical economic reforms and painful budget cuts. That's why they would be aimed at countries that are fundamentally in decent health, but suffering from increased risk-adversity among investors.
Such flexible short-term loans could help Italy and Spain if they had to come up with billions of euros to recapitalize their banks, also reassuring private investors that they will get their money back.
AP Business Writer Greg Keller contributed to this report.