DUBLIN, Ireland - European leaders were scrambling yesterday to find a new path to a more powerful and manageable European Union after Irish voters rejected a treaty meant to bolster the alliance's government.
The rejection threw into doubt nearly a decade of efforts to overcome widespread public skepticism and develop a European constitution.
The reforms would create a powerful European presidency and diplomatic corps and improve cooperation on law enforcement and defense.
Because the measure must be ratified by all 27 member states of the alliance, Ireland's rejection struck a potentially fatal blow.
European leaders face the prospect of resubmitting the treaty to hostile Irish voters or, to the dismay of all, renegotiating it again.
"It is clear that the Lisbon Treaty will not take effect on Jan. 1, 2009," Luxembourg Prime Minister Jean-Claude Juncker, the EU's longest-serving leader, said after Irish voters in a referendum on the treaty rejected it by a margin of 53 percent to 46 percent.
"It's a bad choice for Europe, and for Ireland," Juncker said.
Alliance leaders were scheduled to meet next week, and most vowed to proceed with winning ratification of the treaty.
In the end, however, the Irish vote left European governance in the same place it has been almost since the EU's birth: in paralysis and limbo.
The European Union was formed in 1993 as a loose alliance of countries seeking to expand three decades of economic cooperation into the spheres of security, justice, human rights and border control.
Since then, it has grown in size, complexity and its ability to compete with world powers.
But especially after 10 new nations joined in 2004, the EU's traditional rule by consensus has become unwieldy, even as demands grew for a more cohesive foreign policy, more assertive military cooperation and decision making that could not be held hostage to a single dissenting nation.
Eighteen countries have fully or partially ratified the treaty, which allows decisions to be taken in many areas by qualified majority vote.
Ireland was the only nation whose constitution required a referendum, and the 1.6 million citizens who voted Thursday have thrown a wrench into a constitution for more than 490 million residents of Europe.
"I am extremely mindful today ... of our European partners for whom this vote will represent a considerable disappointment and a potential setback to many years of effort," Prime Minister Brian Cowen said. "Ireland has no wish to halt the progress of a union which has been the greatest force for peace and prosperity in the history of Europe."
He said the Irish government will "reflect on the implications of this vote," and consult next week at a summit of European Council leaders on how to proceed next.
One option would be to call another vote, considered unlikely given the high turnout and definitive defeat. Another would be to launch a new round of negotiations on the reform, which failed once before with public rejection in France and the Netherlands in 2005.
French President Nicolas Sarkozy and German Chancellor Angela Merkel called for continuing the process of ratification by other member states, which are considering the treaty through their parliaments.
In some cases, heads of state must also sign the document.
Britain is next, with a vote scheduled in the House of Lords next week.
But British opponents of the European treaty were signaling their intent to use the Irish defeat as ammunition to call for a referendum in Britain.
The defeat followed a major push for approval by the Irish government, which contended that the country's economic boom over the past decade has been fueled by access to the European market and the availability of billions of euros in EU subsidies for agriculture and infrastructure.
But a coalition of Irish nationalists, right-wing Catholics, businesspeople and groups leery of the treaty's potential impact on taxes, agriculture and abortion policy argued against the treaty.
Donny Mahoney and Kim Murphy write for the Los Angeles Times