When Margaret Beckett, the foreign secretary, sits down for dinner tonight in Luxembourg with her 26 European Union colleagues, she will fire Britain’s opening shot in what promises to be a bitter week-long battle over the future of Europe.

The dinner, in a dull conference centre, will not be the most glamorous event Beckett has attended, and it could be one of her last: she is not expected to survive in the position once Gordon Brown takes over as prime minister on June 27.

But the meal for foreign ministers marks the unofficial start of this week’s EU summit (things officially get under way in Brussels on Thursday) and on the table is a reheated version of the European constitution proposed three years ago and scuppered by French and Dutch voters 12 months later.

What Britain agrees to sign up to will do much to determine the success or otherwise of Brown’s first year in office. More than that, say critics, it could go down in history as a crucial juncture in the development of a European superstate.

A bluffer's guide to the EU treaty

Our correspondent hacks through the verbiage to explain what happened at the EU summit and what it means

• Patchwork deal proves Europe cannot heal its deepest wounds

Background

• Unconstitutional

• Fresh start or revived constitution?

• Merkel’s dream; Britain’s nightmare

• Brown’s first test: how to avoid an EU constitution

• Europe divided over summit plans

By Thursday, Britain’s fate will be firmly in the hands of Tony Blair, attending what will be his last EU summit as prime minister. Germany, the country most keen on the constitution and a federal Europe, is host of the event and is expected to make a fuss of him.

Three months ago Angela Merkel, the German chancellor, presented Jacques Chirac, the outgoing French president, with an antique commemorative beer mug, dating from the time when Napoleon was fighting in Egypt. Blair, after 10 years in power, can also look forward to something to put on the mantelpiece – and perhaps much more besides.

Yesterday it was confirmed that the French president Nicolas Sarkozy has discussed with Merkel and other EU leaders the idea of making Blair the EU’s first full-time president. It is a role that Blair, who has long honed a presidential demeanour, would surely covet. Indeed it is a job that – with the right powers attached – could arguably make him more influential on the world stage than the British prime minister.

Yet the job of full-time European president does not exist and will not exist unless Blair signs Britain up to the reworked constitution this week. The question is, can he do it without selling Britain and his mate Gordon down the river?

A blueprint of the proposals circulated by Merkel to capitals on Thursday outlined the battles to come by including a six-point list of unresolved issues.

Her gambit put Eurosceptics on the back foot by pledging to protect “much of the substance” of the failed constitution rejected two years ago and making it clear that she had the support of the majority of the 27-nation bloc to revive it.

True, it is no longer being called a constitution, that being regarded as too provocative, but many see her “treaty on the functioning of the union” as a constitution in all but name.

Anybody who doubts that only had to listen to Valéry Giscard d’Estaing, the former French president who headed the convention that drew up the original document. He told the French newspaper Le Monde that the public was being led “to adopt, without knowing it, the proposals that we dare not present to them directly”.

Nigel Farage, leader of the UK Independence party, put it more bluntly. “In essence this EU treaty will contain the provisions of the failed constitution but drop the C-word itself,” he said. “It is all an exercise in deceit.”

That may overstate it, but that the new document contains traps for Britain there is no doubt. Top of the list of problems for Blair is a German plan to keep the “legally binding character” of the charter of fundamental rights as a “cross-reference” in the new treaty.

Britain opposes this as it would make the right to strike enforceable in European courts and undermine other UK laws. But most member states, including the 18 who ratified the original constitution, strongly support it.

A further potential blow to Britain’s interests is a proposed clause that would give the EU a “single legal personality”, allowing it to join international organisations or sign international agreements and, say constitutional experts, thus weaken the role of nation states.

Ironically, any ambitious future president of the EU would, one presumes, be keen to see this clause implemented as it would significantly extend his powers.

After an initial discussion of Merkel’s blueprint at the foreign ministers’ dinner tonight, the most sensitive issues will be left to EU leaders on Thursday, when they gather for what is already being described as a “three-shirt” summit, with the expectation that talks will drag on until well in into the weekend. “Croissants at dawn are likely on Saturday,” said one EU diplomat.

While Blair will be in Brussels negotiating the new treaty, Brown will be biting his fingernails in his Scottish constituency, wondering whether he will be inheriting a poisoned chalice.

“The main difference between them is that one can walk away from whatever is decided, while the other will have to deliver,” said one Whitehall observer.

“Blair only has to worry about his legacy – and it wouldn’t be a huge part of that anyway – whereas Brown has the potential nightmare of pushing it all through.”

Though some commentators speculated last week that a final Blair-Brown bust-up was in the offing, the evidence suggests that the two men are as one on the issue of the new treaty and have agreed that Britain should at least appear to give away little.

Indeed some suspect that the only reason Blair has left it this long to leave Downing Street is to protect Brown from the political fallout that inevitably follows any significant EU summit. The strategy all along, say this camp, has been to fix things so Brown starts as prime minister with as few thorny issues as possible to deal with and a full stock of political capital.

A senior Foreign Office official who has sat in on the weekly strategy meetings on the constitution, which started as long ago as Christmas, said: “I have been really impressed with the way they have worked together on this. For once they are both on the same page.”

The bottom line for Brown, he added, was to avoid having to hold a referendum on the treaty at all costs. “We can’t have one, because we’d lose. It’s that’s simple,” admitted a Brown aide.

The Conservatives, in contrast, will almost certainly call for a referendum on the issue no matter what decisions are made but Brown’s camp are determined to tough it out.

“How can the Tories call for a referendum on this, when they voted against holding a referendum on the Maastricht treaty, which contained far more extensive changes? I cannot see how their position can change so dramatically,” said Geoff Hoon, the minister for Europe.

But the fear is that this will not cut much ice with voters or the Eurosceptic press. Open Europe, a nonparty think tank, says that the creation of permanent EU president and a single foreign policy representative carries big implications.

The organisation’s director, Neil O’Brien, said: “This isn’t just about a change of name. These would be very powerful new posts, and mean that decisions over crucial foreign policy issues would be increasingly taken in Brussels.”

Blair and Brown have repeatedly set out their “red lines” on the treaty, claiming they will not give up the British veto on foreign policy, employment and criminal law, or allow the charter of fundamental rights to creep into British law. “In relation to the European charter, I will agree to nothing that allows Europe to alter our laws without the consent of this house,” Blair told MPs last week.

It was a sweeping statement that left experts little the wiser as to where he might be prepared to compromise. Perhaps not surprisingly, his aides have not been prepared to elaborate on precisely what will and will not be negotiable.

Yet close observers of summits fear that a sleep-deprived Blair, under intense pressure from other member states and with an eye to his legacy, could still cave in early on Saturday.

“If I were Gordon, I would be very worried that Blair will agree to something in the heat of the moment that he did not intend,” said Sir Christopher Meyer, a summit regular when at the Foreign Office. “The potential domestic political ramifications for Gordon are huge.

“I went to loads of these summits with Geoffrey Howe and John Major and I know how complicated it gets. The pressures on you are huge. You have to have a bottom line, and stick to it. You have to be prepared to be isolated.”

In the last week Hoon has been dispatched for meetings with his French and Dutch counterparts, as well as representatives from the Polish government. The aim is to ensure the summit succeeds, or at least that the blame is shared if it fails.

Britain, along with the Czech Republic, the Netherlands and Poland forms a gang of four countries seen to be “troublesome” by the 18 countries who have already ratified the constitution. The Poles are the true wild card and there is little desire in Brussels to appease them. While Britain’s main interests have been included in Merkel’s list, the Poles’ main gripe over voting rights is a glaring omission.

In the past few weeks the ruling Kaczynski brothers have been brandishing the surreal battlecry “square root or die”– a reference to the new voting system demand by Warsaw that would see votes calculated on the basis of a country’s inhabitants in relation to its surface area.

The Kaczynksis face widespread opposition to opening the complicated question of voting rights over fears that this will unravel everything and scupper a quick agreement.

“If the Poles stand firm then it will be the biggest threat to the deal. What the Poles want is what nobody else wants. It is very difficult to see a game or trade-off,” said Jacki Davis of the European Policy Centre.

“Tony Blair wants a deal next week but if there is no deal then he will go to strenuous efforts to make sure the Poles get the blame.” The Czechs, who support Warsaw, are expected to cave in during summit talks, as are the Dutch, who want the guarantee of a “red card” for their parliament to be able to veto EU laws.

Blair, despite his desire to go out on a high note in Europe, might have to accept failure. “It is perfectly possible that the divisions over the content of this treaty will simply be too great,” a senior Foreign Office official admitted.

Denis MacShane, the former Europe minister, believes it is highly unlikely that the prime minister can pull off a genuine coup. “Each time I went with Tony Blair into that concrete blockhaus in Brussels he groaned,” MacShane said. “They might as well have inscribed ‘Abandon good spirits all ye who enter here’ over its glass revolving door.

“Each one of the 27 national leaders enters thinking he or she will emerge with a big victory. They never do, despite their bravura playing to the national galleries back home. Compromise and mutual concession is the dirty little secret at the heart of Europe.”

Even for Blair, this EU treaty may be a compromise too far. But Charles Grant, director of the Centre for European Reform, says that even if Britain manages to head off pressure for significant treaty changes this year, the issue will return to haunt Brown.

“There are some people in Belgium and Luxembourg who think it would be outrageous for Britain not to accept things we’ve signed up to in the past,” he said. “Even if there is a willingness to get this one out of the way, this is not the end of treaty change in Europe.”

Jose Manuel Barroso, the European commission president, last week urged Blair to “have the courage” to stand up to British public opinion and sign the treaty. “We have to stand up in front of our national public opinions, not give up to some of the populisms we have in our member states,” he said.

Sunday Times-YouGov poll

Who should decide whether Britain backs a new European Union treaty?
UK parliament 17%
Voters in a referendum 70%
Don’t know 13%

Would you vote for or against a new treaty?
For 21%
Against 43%
Would not vote 3%
Don’t know 33%

YouGov surveyed a representative sample of 1,753 voters, online, on June 14-15

The whys and wherefores of a European constitution

Q. The EU constitution was supposed to have been killed off two years ago when French and Dutch voters rejected it. Why is it back?
A. EU leaders promised to try to push through changes despite the referendum “no” votes. Angela Merkel, the German chancellor, said she would make this one of the priorities of her country’s six-month presidency of the EU, which started in January.

Q. It is not called a constitution any more, so are the proposed changes only minor?
A. Some symbolic ideas have been abandoned, including enshrining Beethoven’s Ode to Joy as an EU national anthem and formally adopting the EU flag. It will be called a “treaty on the functioning of the union” rather than a constitution. But experts say it retains 90% of the original proposals and Valéry Giscard d’Estaing, the former French president and drafter of the constitution, said the public was being persuaded to adopt the constitution’s proposals “without knowing it”.

Q. What are the proposals?
A. Some, which have been accepted by Tony Blair and appear acceptable to Gordon Brown, include the appointment by EU leaders of a permanent EU president of the council of ministers. He or she will have responsibility for arranging summits and pushing the agenda forward. The current six-month revolving presidency, shared by member states, will stop. The EU will also have a single foreign policy representative, although he or she will represent Europe only on issues upon which all countries agree. Countries will lose automatic entitlement to have an EU commissioner, cutting the number from 27 to 15. More areas of EU policy will be subject to majority voting, preventing countries from using their blocking powers.

Q. Does that mean Britain will be forced to adopt policies even if the government objects?
A. In some cases, but there are likely to be UK opt-outs on justice, home affairs and rights for migrant workers.

Britain will object to any attempt to make foreign and security policy subject to majority voting.

Q. What are the real sticking points?
A. The treaty aims to give the EU its own legal status or “personality”, meaning it could enter into treaties with other countries in its own right. Germany is attempting to sneak the charter of fundamental rights into the treaty by giving it legal force.

Q. What is in the charter of fundamental rights?
A. Potentially a great deal. It could allow unions to challenge Britain’s labour laws by providing new minimum standards on working conditions, including holiday entitlements, the right to strike and rest periods. It could also impose new burdens on the National Health Service, giving everybody the right to preventive healthcare and increasing the scope for legal action over the quality of treatment. It could increase social security entitlements, particularly for EU workers in other countries. Some clauses ostensibly aimed at preventing eugenics could impose restrictions on IVF clinics, the paying of sperm and egg donors and the use of embryos.

Q. If Britain objects to these things, will the new treaty be abandoned?
A. Eighteen EU members ratified the old constitution and four more were ready to do so. France and Holland know they cannot go back to voters with what looks like a reheated constitution. Poland is angry about changes that will reduce its voting power and the Czech Republic is sceptical. Britain is in a minority but not alone. The “maximalists”, who want the old constitution, may back down to get a small-scale treaty agreed.

Q. Will there have to be a referendum in Britain?
A. Brown will avoid it at all costs, arguing that EU treaty changes have never required UK referendums in the past. But critics will say that even the changes Britain is prepared to sign up to represent a significant step towards a superstate.

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