Now, as the Netherlands appeared set Wednesday to reject the charter, too, the 25 EU governments may finally be forced to outline a blueprint for the future.
EU leaders intensified negotiations to salvage the treaty as the Dutch voted on the constitution 72 hours after the French 'no.' Opinion polls indicated about 60 percent opposition in Holland, even higher than the 55 percent in France.
So far, the EU has refused to discuss a Plan B, fearing that would embolden naysayers. Observers say alternatives might include a redrafting of the treaty, a drive to make France and Holland vote again, or even a Europe-wide referendum on a single day.
On Wednesday, EU leaders showed signs of scrambling to devise a game plan, which would likely be formally unveiled at a June 16-17 European summit.
In Brussels, European Commission President Jose Manuel Barroso discussed the fate of the constitution with his 25-member EU executive, which backed his view that the treaty is not dead but that its ratification must continue in all EU member nations.
"It is up to the member states to decide what to do now," said EU spokeswoman Francoise Le Bail.
Luxembourg Premier Jean-Claude Juncker, whose nation holds the rotating EU presidency, held one-on-one meetings with his counterparts from Slovakia, Portugal and Austria at a Luxembourg chateau where he will meet all EU leaders before he chairs the upcoming European summit.
The way ahead looks very fuzzy.
Austrian Chancellor Wolfgang Schuessel's proposal this week for an EU-wide referendum has already been rejected once. A panel of 105 representatives of EU governments, legislators and the European Parliament that wrote the constitution found the idea legally unfeasible.