The president of the European Council said Friday that a new intergovernmental treaty meant to save the euro currency will include the 17 eurozone states plus as many as six other European Union countries — but not all 27 EU members.

The failure to get agreement among all the members of the European Union at a summit meeting in Brussels reflected in large part a deep split between France and Germany on the one hand and Britain on the other. France and Germany are the two largest economies in the eurozone; Britain does not use the euro as its currency.

French President Nicolas Sarkozy said early Friday he would have preferred a treaty among all the members of the European Union. But that could not be achieved, he said, because the British proposed that they be exempted from certain financial regulations.

"We could not accept this" because a lack of sufficient regulation caused the current problems, Sarkozy said. The new intergovernmental accord should be ready by March, he said.

Still, German Chancellor Angela Merkel praised the plan.

"I have always said, the 17 states of the eurogroup have to regain credibility," she said. "And I believe with today's decisions this can and will be achieved."

The summit meeting in Brussels was viewed as a critical step in the effort to save the euro. The currency is losing the trust of the international financial markets, who fear that some debt-laden euro countries may ultimately be unable to pay their debts.

That doubt means that the governments of countries viewed as in a precarious state must pay higher interest to borrow the money they need to carry on — and that, in turn, makes their budget deficits even worse and can be unsustainable in the long run.

EU officials believe that one way of regaining market trust is to beef up the financial governance overseeing the eurozone countries and their budgets. Any intergovernmental treaty will be an effort to ensure that national budgets are brought into balance and large debts are not run up again.

And the officials believe another way to regain the trust of investors is to have enough money on hand to guarantee that eurozone countries won't default on their debts.

Toward that end, Herman Van Rompuy, president of the European Council, said some EU countries would provide up to euro200 billion ($268 billion) in extra resources to the International Monetary Fund, to be used to help countries in dire straits.

Sarkozy also said the EU's two bailout funds, meant to rescue countries having trouble refinancing their debts — the European Stability Mechanism, or ESM, and the European Financial Stability Facility, or EFSF — would be managed by the European Central Bank, though the details still need to be worked out.

The French president said work was proceeding on an "intergovernmental accord" among the 17 countries that use the euro plus as many as six others, not counting Britain, Hungary, and so-far undecided Czech Republic and Sweden.