The Obama administration won’t contribute more to the International Monetary Fund for a possible bailout of Italy or Spain, U.S. officials said Friday after reviewing the new crisis agreement among European officials.

European Union nations meeting in Brussels have agreed to lend as much as $270 billion to the IMF to ensure that it has enough in hand should one of the larger euro-zone nations have trouble raising money in the bond markets.

That decision was part of a broader agreement announced Friday among leaders of 26 European countries — minus Britain — to shape a treaty that calls for strict fiscal limits to try to save the euro. British Prime Minister David Cameron rejected the deal after Germany and France turned down his demands to include protections for his nation from future financial regulations. Britain does not use the euro.

Regarding the loans to the IMF, European leaders said in a statement that along with money from their national coffers, they “are looking forward to parallel contributions from the international community.”

That may well involve loans to the IMF from cash-rich Asian nations such as China that have large caches of foreign reserves, or from emerging powers such as Brazil that are doing well economically and eager to play a more influential role in the IMF. Those nations and others have said they would consider contributing more to the IMF but first wanted to see what Europe did for itself.

But the infusion of new cash apparently won’t involve the United States.

Treasury Secretary Timothy F. Geithner has said throughout the euro crisis that the IMF is adequately funded and that Europe has the financial resources to handle its own problems.

A senior U.S. official said that the agreement in Brussels does not change that conclusion and that the administration does not plan to make a bilateral loan to the IMF to help fund possible bailouts in Europe.

The agreement overall, the official said, speaking on the condition of anonymity because the European programs are in negotiation, represented a positive step in Europe’s ability to contain its financial problems.

On Wall Street, major market indexes closed the day with solid gains of more than 1.5 percent. A better test of investor trust in the Brussels agreement will come when countries such as Spain, Germany and Italy return to bond markets in coming weeks to raise money.

The United States is considering other ways to boost the IMF’s financial firepower that would not require it to contribute taxpayer money to the agency. It plans to work out those ideas among finance ministers of the major economic powers in time for a February meeting.

The United States is the IMF’s major shareholder, with a roughly 16 percent stake in the agency. It contributed to a 2009 emergency expansion of the agency’s resources that was assembled to battle the financial crisis that followed the collapse of Lehman Brothers. It also approved a general funding increase for the agency last year, though the U.S. contribution to that has not yet passed Congress.

Some congressional Republicans have expressed concerns about any further contribution to the agency, particularly if it is linked to Europe’s debt problems.

The European decision also raises a host of questions surrounding when and how the extra money will be provided to the IMF and how it will be used.

European Central Bank President Mario Draghi said Thursday that lending money to the IMF strictly for the purpose of recycling it to other European countries — essentially disguising direct loans between countries as loans to the IMF — could violate Europe’s basic treaties.

In a statement Friday morning, the IMF said the money from Europe would go into its general resources account, which is available to help any nation that needs it.

If Italy or Spain runs into trouble as they sell the hundreds of billions of dollars in bonds needed to run their governments in coming months, they would have to appeal to the fund for help in the same way that Greece, Ireland and Portugal have done in the past 18 months — and be subject to the same sort of IMF oversight.

IMF Managing Director Christine Lagarde said in a statement that she welcomed the summit decisions in Brussels and that the contribution to the IMF would help the fund “fulfill its systemic responsibilities” in stabilizing the world financial system.