Mrs. Merkel, a central player in efforts to rescue Europe’s single currency, was addressing the German Parliament before a meeting next week in Brussels, when Europe’s leaders will try again to find a politically palatable solution to the crisis. Threats of a credit squeeze and default by deeply indebted countries have roiled global markets and brought down governments, most notably in Greece and Italy.

While Mrs. Merkel called for quick changes, “if possible by the end of the year,” historically there has been nothing speedy about the remedy she proposed: fixing the “mistakes of construction” in the euro zone by altering the treaties that govern the European Union. It took years to negotiate and ratify the last major change, the Lisbon Treaty, after the failure of the previous effort to write a European constitution.

But Europe’s leaders are evidently hoping to use the shadow of impending crisis to speed the process. Mrs. Merkel’s call for a new treaty tracked with a speech made Thursday by President Nicolas Sarkozy of France, with whom Mrs. Merkel has been negotiating. Some experts say there are more expeditious ways to effect treaty changes than the traditional path followed by the Lisbon Treaty.

Mrs. Merkel’s assessment of what was needed appeared to be well received by European financial markets, which had been strengthening this week anyway, partly on hopes that European leaders would address the crisis. The Stoxx 600 index, a broad barometer, rose 1.2 percent for the day and 9 percent for the week, its biggest gain in three years, Bloomberg News reported. The euro was trading at $1.348, up from $1.346 on Thursday.

Mrs. Merkel continued to oppose so-called euro bonds backed by all 17 members of the existing currency union, which embraces many different levels of economic strength ranging from struggling Greece to the export-driven German economy, which is seen as the powerhouse of Europe. She called the idea of euro bonds “unthinkable.”

Her comments with regard to the European Central Bank were more ambiguous. She defended the independence of the bank and said she would not comment on its decisions. A report on Friday in the newspaper Süddeutsche Zeitung said she was prepared to tolerate more aggressive action by the bank to steady the most indebted nations.

Some financial experts have also speculated that Mrs. Merkel and Mr. Sarkozy are trying to create the impression of irresistible momentum toward structural change in Europe as political cover for the central bank. If the public and the bank believe that steps are being taken to rein in irresponsible governments, the experts say, then the bank’s German-influenced leadership is more likely to act decisively.

The president of Germany’s powerful central bank, Jens Weidmann, said Friday that the long-term solution to the euro crisis was the responsibility of governments, rather than of the central banks. Countries must be willing to cede some control over their spending policies, he said, for example by agreeing to automatic tax increases if their budget deficits rise above limits agreed to by treaty.

If political leaders announce a credible plan this coming week, he said, “calm could quickly return to markets.”

The urgency of the crisis, which has forced Greece, Portugal and Ireland to take bailouts and has driven up borrowing costs for Italy to unsustainable levels, is apparent in the flurry of meetings between European leaders. On Friday, Mrs. Merkel sat down with Chancellor Werner Faymann of Austria, and Mr. Sarkozy and Prime Minister David Cameron of Britain held talks in Paris.

Mr. Sarkozy tried to reassure Mr. Cameron about French and German plans to promote a new European Union treaty to enforce budget discipline. Britain, which is part of the European Union but not the euro zone, is worried about the creation of a “two-speed Europe” if the euro zone countries make agreements just among themselves.

While France and Germany see closer European oversight of national budgets as the key to calming the storm on the bond markets, Mr. Cameron is under pressure from his Conservative supporters at home to protect British interests and sovereignty. “We’ll see what happens next Friday, but I’m absolutely convinced the bottom line for me is always what is in the best interests of the U.K. and how I can promote and defend that,” he said, referring to the summit meeting next week.

Nicholas Kulish reported from Berlin, and Steven Erlanger from Paris. Alan Cowell contributed reporting from London, and Jack Ewing from Frankfurt.

Article source: http://feeds.nytimes.com/click.phdo?i=355239a00b797809ba331ba4865e8afc