EU constitution: What happens without it?

By Tim Franks BBC Europe correspondent

What will happen to the EU if it fails to agree on the text of a constitution? And what will follow if the UK, or any of the 25 member states, fails to ratify this constitution?

The logic is simple enough. Once, Europe numbered six. This month it grew to 25. Old structures cannot bear the new weight of numbers.

Across Europe, the greatest controversy is precisely over the proposed institutional changes.

Europe could still function without a constitution

Poland and Spain - both medium-sized countries - were distraught at the prospect of losing their disproportionate voting muscle within the forum for member states.

Smaller countries go faint at the thought of there no longer automatically being a Commissioner - a senior EU official - from every member state; odd that, given that these commissioners are supposed to act completely outside national interest.

Even if you think all this makes sense, you cannot argue that the EU will be left mid-air without this constitution.

There are decades of treaties to soften the fall. You can debate whether the EU will work as well as it might. But it will work.

Referendum danger

Will the constitution ever come into effect? That is another question.

After agreement among the leaders, there needs to be approval by parliament or the public in each member state.

This constitution is supposed to be the answer - the magnet that will draw the union closer to its people. If now the people reject the remedy, the EU will have failed the test it set itself

The odds lengthen when it is a referendum. Several countries have already announced they are having one.

Let us be clear, even at the risk of rudeness. History has shown that it matters less when a smaller country votes no to a new EU treaty. If the UK was to vote no, it would matter hugely.

France and Germany are talking darkly - actually they say it is helpfully - about the UK being chucked out of the EU if it does not vote yes within two years.

There is no legal provision for that in this constitution. Nor is the idea going to be popular across all member states.

Two-speed Europe

What is more likely is an extension of what exists now inside the EU - a two-speed Europe.

There is already an inner core of countries which belong to the euro, or have removed internal border controls.

Now there is talk of "enhanced co-operation" - a group of states pushing ahead in new areas.

It may be an answer, but it will cause uncertainty.

Will the EU's rigid institutions cope with the strain of a Europe working at different speeds?

Will small countries, and newer member states be able to resist the siren whir of the Franco-German motor, even if they want to?

If the inner core grows and grows, how isolated will the outer core become?

Will Tony Blair's dream of the UK at the heart of Europe be smashed forever?

More immediately, the EU would have to confront the evidence of continuing public alienation. Faith in the European Union is falling across the member states.

This constitution is supposed to be the answer - the magnet that will draw the union closer to its people. If now the people reject the remedy, the EU will have failed the test it set itself.

Other reports by Tim Franks on the EU constitution:

Part Four: Dealing with rights

Part Three: Making sense of Europe

Part Two: Power struggles

Part One: Blueprint for superstate?