The Big Question: Is the EU constitution coming back, and what would it mean for Britain?

Why are we asking this question now?

Germany has taken over rotating presidency of the EU and put revival of the constitution at the heart of its six months in the hotseat. Yesterday, the German Chancellor, Angela Merkel, said it would be a "historic failure" if the impasse over the constitutional treaty is not broken by early 2009. She wants detailed plans on how to do this agreed by June.

But isn't the constitution dead?

In the minds of British politicians, it is. John Reid, the Home Secretary, described the document as a "dead parrot". To come into force all EU nations have to ratify the document and, after "no" votes in French and Dutch referendums, the EU decided on a "pause for reflection". Since then there has been, as one wag put it, a lot of pause and not much reflection.

The trouble for Britain is that lots of countries do not want to consign the document to the bin. Eighteen of the 27 EU nations have already ratified it, including two (Spain and Luxembourg) via referendums. They want to revive the text - or something as close as possible to it - and will hold a meeting of "friends of the constitution" in Madrid next week to press their case.

So what will happen now?

Actually, nothing very much for a few months. Talks between officials ("sherpas", in the jargon) from each of the 27 countries and the German presidency start in Berlin next week. But nothing concrete can be put on the table until the early summer. The reason for this is that France is holding presidential elections in April and May and, until a new leader is installed in the Elysee, little can be agreed. Because France is a founder member of the EU, and because it is one of the two nations that rejected the constitution, its backing for any potential solution is vital.

Who else has a problem?

In addition to the UK, and France and the Netherlands, who both rejected the constitution in 2005, referendums on a successor to the constitution might be lost in Eurosceptic Denmark and the Czech Republic if they were to be held. Poland was thought to face an uphill battle ratifying any test, but Poles are warming to the EU because of the rights it has brought for workers to move to the UK and Ireland, and because of European subsidies. Irish politicians are confident they could win a plebiscite.

Do we really need a new treaty?

Most people agree that the EU's Heath-Robinson-style decision-making machinery, originally designed for six nations, is creaking under the pressure of 27. But whether all the changes outlined in the constitution are necessary is debatable. Among other things, the constitution would change the voting system for member states to align it to nations' population; create a permanent president of the European Council; and establish a new European foreign minister. Yesterday Ms Merkel said it was impossible to contemplate further enlargement of the EU without a change in the EU rulebook. But Britain argues that actually the union operates well enough under its old rules, and the arguments for institutional reform are "overstated".

One element that requires change is the size of the European Commission. Currently, each country has one European Commissioner, but there is a ceiling of 27, at which point a smaller Commission should be created. That means a change needs to take place before a 28th country (Croatia is next in line) can be admitted. The UK argues, however, that, if necessary, changes to the size of the Commission could be agreed as part of Croatia's accession treaty when it joins the EU.

What will the Germans do?

The best prospect is to get agreement on a "mini-treaty" rather than a "constitution". Calling the document a "mini-treaty" and scaling down the content may mean that several nations can avoid referendums. Moreover, the same text cannot be put to the French and Dutch voters again with any hope of success.

The German strategy seems to be to extract most of the rhetoric from the preamble of constitution which lays out the objectives of the EU. Practical changes outlined in the constitution would then be left for the mini-treaty, which would look to French and Dutch voters rather different from the constitution they rejected.

Nicolas Sarkozy, the centre-right candidate in the French presidential elections, says he backs this approach and that such a document would not need to be endorsed in a referendum. However, his socialist rival, Ségolène Royal, said yesterday she would still put such a document to the people if she is elected.

Just what would be in a 'mini-treaty'?

Germany knows it cannot add material to the constitution because that would mean the 18 countries that have ratified it would have to do so again. So the issue is how much is taken out. The UK wants a minimalist document and says it makes no sense to have a treaty that will require a referendum. It has not, however, defined precisely what would trigger a plebiscite in the UK.

One problem the Germans face is that the more they tinker with the content of the constitution, the more risks they take. The current text is the result of painstaking negotiation among EU countries which included a whole series of trade-offs. The more that is reopened, the greater the danger that the whole exercise will unravel.

What are the chances of a deal?

Medium. Sceptics hope that it proves impossible to reconcile the position of the 18 who have ratified the constitution with the nine who have not. But, if the French and Dutch can find a compromise with the 18, then the exercise gains momentum and comes alive again.

How would this affect Britain?

While other big nations - including France - have problems, the British government can hide behind them. If it finds itself alone or, say, with one small country such as the Czech Republic, then it could become a realistic proposition for the rest of the EU to go ahead without us. That could consign the UK to an outer rim - or perhaps even expulsion - were it to fail to ratify the new treaty.

British tactics are becoming clear. The Government will try to limit any new treaty to one that it feels it can ratify without a referendum. If it fails in that task, it will try to be the final country to put the document to the people, presenting British voters with the question: do you want to stay in the EU or leave?

Does the EU need a new constitutional treaty?

Yes...

* The decision-making machinery of the EU was designed for six nations, it cannot cope with 27

* Without changes to streamline the EU, some of the member states will not permit it to expand any further

* Changes such as the creation of an EU foreign minister will increase Europe's clout on the world stage

No...

* The people of France and the Netherlands have rejected the constitution and their views should be respected

* The EU is managing to work without the constitution, which demonstrates that the changes are not vital

* A new treaty would boost European integration at a time when voters are increasingly sceptical about the EU