Tony Blair has only himself to blame for the mess he has landed this country in over a referendum on the European Union amending treaty. During the negotiations for an EU constitution in 2003 he refused a referendum. He surprised everyone when, in 2004, having accepted the draft treaty establishing a constitution for Europe, he changed his mind under pressure from the other two political parties.

“Let the people have the final say,” he declared.

President Chirac was furious at being upstaged and called a referendum in France. Blair subsequently announced that there would be a referendum in the UK even if the French and the Dutch voted no.

After the resounding defeat of the constitutional treaty in France and Holland, Blair dropped this commitment. Then, in the 2005 general election, the Labour party manifesto had a commitment to a referendum if the constitutional reforms reemerged on the EU’s agenda.

Now Blair, as one of his last acts as prime minister, once again rejects a referendum. Six different positions on a referendum in four years. Is it any wonder that disillusion and cynicism have grown in British politics?

It is worth remembering that the Liberal Democrats and the Conservatives also promised a referendum in their election manifestos.

We are now going to watch the dismal spectacle of Labour MPs being whipped to vote against their manifesto. We will also see some of the very committed integrationists in the Liberal Democrat party – and perhaps a few Conservatives – trying to avoid a referendum by voting against or abstaining when David Cameron tables a motion in the House of Commons for a referendum.

It will not be easy for these MPs to avoid commitments they have already made to their constituents during the 2005 election campaign. Many people then, sensing that their MPs might be making only a ritual commitment to a referendum, questioned them in public meetings or wrote to their MPs with the intention of firming up their commitment. Records are available to show that there are a large number of MPs who were deeply committed to a referendum. They will be in serious trouble in their constituencies if they go back on their word.

Of course the spin and gloss that are being put on the treaty agreed yesterday are that it is different from the EU constitution negotiated in 2004. There are some differences but what is absolutely certain is that all the major constitutional innovations remain in the new treaty:

- A new post whereby a person who is not an elected head of government can be president of the European Council.

- A massive enhancement of the role of high representative for common foreign and security policy who will also become vice-president of the commission.

- For the first time the granting to the EU of a single legal personality whereby the EU can sign treaties and international agreements in its own right.

- A sizeable extension of qualified majority voting.

These are all significant constitutional matters by any standard. They are also constitutional changes with one purpose in mind: further integration. In the jargon of Brussels it is “pillar collapse”, which means that the separation between the intergovernmental and supranational elements, or pillars, of the European treaties is collapsed in ways that can point only towards ever greater integration in the decades ahead.

I am in no position today, with the ink barely dry on agreements cobbled up in the early hours of Saturday morning, to judge how real are the safeguards on other matters that Blair claims to have negotiated. All I know is that similar hype in the past has been shown within days to be false and the claimed preservation of the British position soon eroded.

Anyhow, we need to see the detailed wording of the proposed treaty after the intergovernmental conference, and even then we need to see the translated version, which has often differed in meaningful ways in the past.

It may be that people of goodwill will differ in a referendum on the interpretation of those words. Some may be satisfied that it is better to accept the overall package than for Britain to say no. But that decision needs to be taken by the British people, as they have been promised by all the political parties.

It is not just those who will vote against the treaty, almost regardless of its wording, who are demanding a referendum. Opinion polls suggest that there is a massive majority in this country who want to take this decision for themselves outside the framework of a general election.

If Gordon Brown follows the same path as Blair he will poison his prime ministership from the outset. It may appear initially that he can get away with it but, even if he can force it through the House of Commons, there will be a risk that the House of Lords will exercise its constitutional right to vote against a measure that runs counter to the manifestos of all three political parties.

Even if the Lords passes the legislation, the real retribution will come for Brown in any general election that is held after the treaty has been implemented – currently planned for January 2009. It is no good Brown talking about a new form of politics, listening to people and strengthening parliamentary democracy if a manifesto commitment can be torn up in front of people’s eyes.

The days are long over when the British people were ready to trust parliamentarians to make these far-reaching judgments about Britain’s ability to retain its independence within the EU. The 1975 referendum started an inexorable popular movement. By the mid1980s there was a growing belief that there should have been a referendum over the European single market. This was heightened in the early 1990s over the Maastricht treaty. But at least a commitment was extracted from all three political parties in the 1997 election that there would be a referendum about going into the euro.

Everyone knows that Blair would have held a referendum at any time during his prime ministership if he believed he could have won a yes vote on the euro. People sense that if they are unable to insist on a referendum on this latest treaty, having been promised one, then at some future date they will also be deprived of a referendum over entering the euro.

For those of us, like myself, who remain convinced that Britain should stay within the European Union, the referendum is a democratic safeguard. If that safeguard is removed, the demand for Britain to withdraw, without even a referendum, will grow.

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