Bitter quarrels over a new constitution threaten to dim hopes that an expanding European Union could speak with a stronger common voice on the international stage.
Spain and upstart EU newcomer Poland have fought hard against Europe's titans to resist voting reforms that would cut their influence. The issue could torpedo a two-day summit that opens Friday in Brussels, designed to pave the way for 10 new members to join a streamlined union next year.
Failure could tempt the EU's larger founders, such as Germany and France, to forge their own path independently of their neighbors.
Hints to that effect from Paris and Berlin may be no more than negotiating bluster, say some analysts. But the pre-summit private breakfast that the British, German, and French leaders were due to hold Friday raised questions among smaller EU members fearful of being steamrollered.
The mood has been soured by veiled threats by Germany and France that they would not look favorably on requests for money from Poland and Spain when the next EU budget is drawn up, if Madrid and Warsaw continue to block reform of the union's voting system.
Behind the harsh words lie deeper concerns by some of the smaller EU members, including several Eastern European nations joining next year, that their voices will be drowned out by their larger and more powerful neighbors, Germany, France, Britain, and Italy.
Those fears were fueled two weeks ago, when France and Germany managed to persuade EU finance ministers to let them violate, without punishment, the 'Stability and Growth Pact' - the rules on responsible economic behavior that underpin the euro. A number of ministers felt they had been bullied by the euro zone's two heavyweights, and recalled how the two countries last year stitched up a deal on agricultural subsidies between them ahead of an EU meeting called to debate them.
Piling on the pressure, German Chancellor Gerhard Schröder said on a visit to Paris this week that the idea of a Franco-German union, which some French politicians have proposed as a way forward should European unity dissolve, was "a vision of the future, perhaps long-term, but interesting."
German Foreign Minister Joschka Fischer warned recently against yielding to Spanish and Polish demands for maintaining a system that will make it easy with 25 members to create 'blocking minorities' to forestall action. Such a situation could force countries wanting to deepen cooperation to act outside the EU framework, he said. "We will have the opposite of what we want, namely a multispeed EU where cracks will appear," Mr. Fischer said.
Valéry Giscard d'Estaing, the former French president who led the two-year constitutional convention that drew up a draft charter, suggested last week that if European heads of government approved a flawed constitution "I do think we would see the gradual falling apart of the European Union."
Though that cataclysmic forecast is not widely shared, a summit breakdown would bury, at least for the time being, the dream of "ever closer union" enshrined in the EU's founding document.
"The political damage would be very considerable," says Peter Ludlow of the Centre for European Policy Studies in Brussels. "There would be real turmoil, and you would see an inclination by France and Germany, and possibly Britain, to experiment with intensive cooperation among certain core EU states. That would demoralize the newcomers."
A refounded European Union on the other hand, guided by a constitution that creates an EU foreign minister and permanent president, would be a "credible force on the international scene, with an ability to speak with one voice in Washington, Beijing, and Moscow," says Heather Grabbe of the Centre for European Reform in London. "It's all about what kind of a union the EU wants to be."
The outcome of the two-day summit remained highly uncertain even as it opened, given the hard-line positions some leaders have adopted over the most difficult question - how big a say each of the 25 countries should have in EU decisions.
France and Germany are insisting on the plan devised by the constitutional convention to simplify the EU voting system, and make it easier to reach decisions, by weighting national votes according to countries' populations. A measure would pass if it were supported by a simple majority of governments so long as they represented 60 percent of the EU's population.
Poland (due to join the EU next May) and Spain, however, are rejecting this reform, preferring to stick to the current system, which gives each of them 27 votes on the European Council - only two less than Germany, which has twice as many citizens.
Both sides of the argument have dug their heels in firmly and publicly, making compromise difficult. Italian Prime Minister Silvio Berlusconi, who holds the EU's rotating presidency and will chair the weekend meeting, promised Wednesday: "[I have] "a formula in my pocket that will recognize Spain and Portugal as great countries. I shall pull it out at the last minute." But he has said he sees only a "55 percent" chance of the summit succeeding.
A number of other issues in the proposed constitution remained to be decided in Brussels and could themselves stall agreement.
Among other contested subjects, a group of Catholic countries, supported by the pope, are pushing to include a reference to Christianity, or at least to God, in the preamble to the constitution. France, however, is implacably opposed to anything that might undermine its separation of church and state.