Last week's trilateral summit between the British, French and German leaders was notable for the brouhaha it stirred up, not its tangible results. But although it achieved little in concrete terms, it was an important sign of how politics will work in the 25-member EU. Groups of countries are likely to get together more often to discuss issues of common interest.

The question is whether these groups will mostly be led by France and Germany--as German Chancellor Gerhard Schröder and French President Jacques Chirac would like--or whether the other EU countries will revolt against big-country domination. The new wrinkle is that Paris and Berlin are hoping to turn their big-country duo into a trio by bringing in London.

With Franco-German increasingly discredited in the past 18 months, this tactic makes perfect sense. To their surprise, Messrs. Schröder and Chirac have found they can't appoint themselves the EU's leaders. Most other countries no longer want to follow them most of the time, and instead have come to resent them. France and Germany teamed up to block reform of the EU's farm budget in 2002. A few months later, they tried to speak for Europe in opposing the US-led war in Iraq--only to be publicly contradicted by the more numerous Atlanticist countries in a letter published by this newspaper. At the end of 2003, Germany and France were again on the other side of a divide from Poland and Spain, this time over the issue of reforming the voting system of the Council of Ministers. And the duo irritated many of their partners by pleading for a suspension of the Stability and Growth Pact's sanctions mechanism when both countries were found guilty of breaching its fiscal rules.

After the talks on a new EU constitution collapsed last December, Mr. Chirac lobbied other European leaders to form a core group along with France and Germany. But he found very few who would agree even in principle. Even among the other founding members of the Union, only Belgium is really enthusiastic about the idea. The Italians, Dutch and Luxemburgers rapidly distanced themselves from it. So Messrs. Chirac and Schröder are courting the British.
If this triangle can agree, they reason, the rest of Europe can follow, because they represent such different viewpoints: the Atlanticist British are the economic liberals; the Germans are more pacifist, slower at economic reform and have closer ties with the eastern countries; and the French look south towards the Mediterranean and are protectionist on agriculture.

But the three leaders are having little luck in finding concrete issues on which to co-operate. That's partly because their policies are so far apart, but also because there is no obvious big project that would galvanize the EU as a whole. Last week's summit, called to forge a joint agenda on economic policy, produced only dull texts that repeat many items already on the EU's 'Lisbon agenda' on competitiveness.

Instead of lecturing the rest of Europe, the French and German leaders need to work on liberalizing their own economies and making them more flexible. But their ability to shape reform elsewhere is also limited. The EU already has firmly established institutions and elaborate rules for its economic and regulatory policies. The main areas left untouched are the ones where London has a fundamentally different view from Paris and Berlin--such as taxation and social security. And outside the eurozone, U.K. is excluded from the major decisions on macroeconomic policy.

In practice, large-country leadership only works in the areas of foreign policy and defense where Britain, France and Germany have the diplomatic clout and military assets to make a difference. The trilateral summit will have a lasting effect only if it deepens co-operation between the three countries' foreign ministries. The triangle has had some notable successes in recent months: They agreed to give the EU a limited military planning capability, and the three foreign ministers together persuaded the Iranians to comply with International Atomic Energy Agency inspections. Next on the list might be a major move on Syria.

Such initiatives are welcome if they boost the EU's ability to speak with one voice in the rest of the world. But the Big Three need to work harder to gain their partners' support. It would have cost the foreign ministers little to take Javier Solana, the EU's High Representative for Foreign Policy, on the plane with them to Teheran; but it would have made the mission a truly European one. The other big countries--Italy, Poland and Spain--will insist on being included on external policy in the future. The smaller countries are also anxious to be involved, because their influence in the world depends on the EU having a common foreign and security policy.

If the big boys try to gang up too often, they will provoke resentful counter-alliances among the other countries. Just before last week's summit, Italy, Poland and Spain and three reform-minded smaller countries sent a letter that implicitly criticized France and Germany's behavior on the Stability and Growth Pact .

Germany has most to lose from alienating the rest of the EU. Berlin's long-term approach to relations with its neighbors has been to build strong partnerships with the small EU members and seek reconciliation with Eastern Europe. But recently Berlin has abandoned its role as the advocate of the small countries' interests. Moreover, after 10 years of building bridges with its eastern neighbors, Germany has seen its relations with Poland deteriorate dramatically since 2002. If Germany throws away all these carefully nurtured ties for the sake of its alliance with France, it could shake the whole architecture of the EU. The whole point of European integration was to domesticate the German giant, not to build up a new hegemonic group.

France has an even greater need to repair its relations with the new members of the Union. The Central and East Europeans are still smarting from Jacques Chirac's comments last year that they missed a good opportunity to shut up about Iraq. France was never enthusiastic about enlargement either. It needs to reassure the new members that it can be a reliable partner.

Instead of pursuing the pipe-dream of forming an exclusive alliance that runs Europe, the Big Three should work harder to find a compromise agreement on the EU's new constitution. The 25-member Union does not need a permanent leadership group. It needs a system that allows better decision-making in the interests of all.

Ms. Grabbe is deputy director of the Center for European Reform in London and Ms. Guérot is director, foreign policy-Europe, at the Berlin office of the German Marshall Fund of the United States.