Continued from page 1

Germany and the Netherlands are open to the option, with Mrs. Merkel suggesting this week that Greece’s second bailout deal might have to be renegotiated. France and the European Central Bank, however, oppose the idea.

International debt inspectors returned to Athens on Thursday to complete a review. Mrs. Merkel has said that any new decisions would depend upon the results of the inspectors’ report, which is not due for days.

Forging consensus over new measures — particularly something as delicate as imposing more severe losses on Greece’s creditors — likely will be very difficult, however.

Indeed, the parliamentary debate on the EFSF in Berlin on Thursday was a feisty three-hour-long affair, reflecting how high tensions in Mrs. Merkel’s coalition were running over the idea of providing more backing to the eurozone’s weakest members.

Frank Schaeffler, a dissenter from the junior coalition partner, argued that bailout measures have worsened Greece’s economic situation.

“Despite all arguments, the first bailout did not make the situation for Greece better, but worse,” said Mr. Schaeffler, a Free Democrat. “Expanding the fund will make the situation even worse.”

Mr. Schaeffler and others long have expressed their concerns, and opposition leaders said going into the vote that if Mrs. Merkel’s coalition had to rely on their votes, it would be a sign that her strife-prone and increasingly unpopular government is finished.

Yet after a night of intense lobbying, Mrs. Merkel’s camp was able to secure a majority of 315 — enough to have passed the measure even without support from the opposition parties.

“This shows the clear determination of the coalition on this issue,” Rainer Bruederle, the Free Democrats’ parliamentary leader. “We have made an important decision for Europe.”

Any future changes to the current fund also will require parliamentary approval, and maintaining that determination will be crucial to making swift, effective decisions to combat the crisis.

In addition, the Bundestag will face another major vote early next year on the fund’s permanent replacement, the European Stability Mechanism, which is due to take effect in 2013. Mr. Schaeffler already has vowed to rally his party to reject the ESM.

Party leaders insist they are not worried by Mr. Schaeffler’s plans, but many analysts have noted that Mrs. Merkel will have to hold her majority together, or Thursday may have only been the first in a series of nail-biting parliamentary showdowns over shoring up the euro.

Geir Moulson and Tomislav Skaro in Berlin and Menelaos Hadjicostis in Nicosia, Cyprus, contributed to this report.