The situation is becoming increasingly dangerous. The European Union, which is facing the most serious crisis of its history, cannot rely on Angela Merkel and Nicolas Sarkozy to establish coordinated policies. And their recent attempts to show solidarity — a botched meeting two weeks ago and a joint press conference in Berlin on 14 June — have been awkward and embarrassing to watch to say the least. The truth is that talks between their two governments are marked by an increasing sense of bitterness on both sides.

Something has changed. Seasoned observers of the Franco-German couple have often remarked that Paris and Berlin like to indulge in small squabbles, which simply add to the pleasure of reconciliation, but we are now seeing the painful emergence of what looks like a more definitive rift. The reality is that in the decades that followed the founding of the Union, the Cold War provided a sufficiently strong incentive for both countries to set aside dissent over issues of currency and the European economy. In the 1990s, when this context was replaced by the uncertainty of a new global order, the appeal on both sides was: "Don't leave out here on my own!"

National politics and cultural differences

But now we have a crisis, which has spotlighted weaknesses in the programmes that have propelled the German Chancellor and the French President to the forefront of national politics. Sarkozy's reform machine has run out of steam and Merkel's Bundestag partners are fighting like cats in a strained coalition government.Things have gone from bad to worse, and if nothing is done, the division between the two countries will continue to widen.

In Berlin, there is a general sense that Germany has to contend with a conspiracy in which the director of the European Central bank (ECB), the president of the International Monetary Fund (IMF) and the Director General of the World Trade Organisation (WTO) – all of whom are French – are siding with Nicolas Sarkozy. At the same time, there has been a lot of grumbling abut the "Club Med" formed by Greece, Spain, Italy and France, and its lenient attitude to poor public finances. But everyone's favourite target remains the incumbent in the Elysée Palace, who is so different to us. We have now reached a point where exasperation in Franco-German relations threatens to undermine the symbolic foundations of the EU, which were laid by Charles de Gaulle and Konrad Adenauer, and later reinforced by Giscard d’Estaing, Helmut Schmidt, François Mitterrand and Helmut Kohl. And it is for this reason that the future of Europe may be in jeopardy.

A world dominated by two superpowers

Strained relations have already had a negative impact on major European projects, that is say the EU's common security, energy and climate change policies. Now we are hearing talk of the end of the euro. Make no mistake: indifference to Europe and antipathy to European policy could very quickly come to the fore, especially in France. And if this does come to pass, we will soon have a world that is dominated by two superpowers — the United States and China — and Europe will left to pack up its much vaunted social model, its soft power and whatever else it planned to offer to the world. Perhaps we might even see a split between Northern and Southern Europe.

Germany will remain the heavy-weight on the continent but it will have to accept a lower position in international rankings. Without Europe, France, which simply has to open up to globalisation, will immediately be forced to contend with dwarf status in the global economy. It is as though the France and Germany have forgotten who they are. Together, they produce close to half of the wealth of the European Union, represent a a third of the population of the EU, and control 31% of the vote on the European Council. It is time to demand a serious effort on the part of their heads of state. They must take charge of their situation in their respective countries and call Europe to order. Nothing less is acceptable. We have had enough sparring and enough joint letters to the press, the President of the European Commission, the President of the European Council and the leaders of G20 countries. We want to hear them say "now we are going back to work in politics."

Paris and Berlin could, for example, make a start by coming to an agreement on how to put an end to three decades of poor public accounting in French national budgets. While France balances its books, Germany could attempt to boost its domestic consumption. And these measures should be implemented even if they do imply a degree of painful adjustment. Thereafter, they could simply pledge that they are both committed to building a common future, and the era of going it alone is now definitively at an end.