'Let the people have the final say. Let the issue be put. Let the battle be joined'

Tony Blair, The House of Commons, Yesterday

Tony Blair promised yesterday to transform the surprise referendum on the proposed European Union constitution into a vote on Britain's place in Europe as he wrong-footed the Conservatives with his pledge to stage the nation's first such plebiscite for 30 years.

The Prime Minister, in the biggest gamble of his political career, vowed that he would still call the countrywide poll even if another EU country scuppered a new treaty by voting "no" in an earlier referendum. But he faced criticism from Labour figures and was mocked by the Tories when he confirmed his biggest U-turn since coming to power in 1997.

Mr Blair declined to spell out a timetable for a plebiscite, which is likely to be held in autumn next year, 30 years after the British people voted by 67 per cent to 33 per cent to remain in what was then the European Community. He even avoided using the word "referendum" in his opening statement to the Commons, saying only that "the people" should have the final say after Parliament had debated the new EU blueprint.

Unless all 25 EU members ratify the constitution, the treaty will be stalled and some MPs suspected that Mr Blair would shelve a British referendum if another country, such as the Netherlands, Denmark or Ireland, rejected the EU blueprint. But asked if he would delay a British vote in these circumstances, Mr Blair replied: "No, of course not. The referendum should go ahead in any event."

Mr Blair appealed to pro-European Tories and the Liberal Democrats to join an all-party campaign to win a "yes" vote in the referendum but appeared in little hurry to set it up. He dismissed the idea of a "double referendum" in which people would also vote on whether to enter the single currency.

The Prime Minister raised doubts about whether EU leaders would approve the constitution at their summit in Brussels in June. Although Spain is ready to compromise in a row over voting power which prevented agreement last December, Mr Blair suggested that Poland might not follow suit.

Explaining his about-turn, Mr Blair conceded that Eurosceptics had been partially successful in spreading "myths" about Europe to persuade people that the EU was a conspiracy aimed at Britain. "It is right to confront this campaign head on," he said.

Mr Blair continued: "It is time to resolve once and for all whether this country, Britain, wants to be at the centre and heart of European decision-making or not, time to decide whether our destiny lies as a leading partner and ally in Europe or on its margins .... Let the issue be put and let the battle be joined." He said "the choice" would become very clear as the debate continued - between Britain playing its full part in the EU or going down a road favoured by the Conservatives which would "change fundamentally" its relationship with Europe.

The Prime Minister made it clear he will try to turn the referendum into a wider question about Britain's place in Europe. He warned that the Tories' opposition in principle to the constitution would lead to Britain having only "associate membership" of the EU. Last night Downing Street added that the vote would have "profound implications for our future in Europe and no one should be under any illusions in that."

Jack Straw, the Foreign Secretary, who was the driving force for a referendum within the Cabinet, said the vote would have "wider implications" for Britain's relationship with Europe but would not be a choice between being "in or out". He insisted that Mr Blair would not have to resign if he lost it.

Amid signs that yesterday's announcement had been rushed out after a hasty consultation between Mr Blair and his cabinet ministers, No 10 refused to speculate on what would happen if Britons were to vote "no".

Neil Kinnock, a vice-president of the European Commission, echoed the disquiet among pro-Europeans when he declared his "deep reservations" about the plebiscite.

"We have referenda in this country when the system of government is to be changed or if the UK's relationship with other EU member states was to change. Nothing is changing on either of these fronts," he told BBC Radio.

He said Rupert Murdoch's newspapers had influenced the decision to hold a referendum "substantially" because their representatives made it clear that they were intent on "continuing to distort" Britain's relationship with the EU. The Murdoch press was "building a boil" and the Prime Minister had taken a decision to "lance it", he said.

A Downing Street source said Irwin Stelzer, a close associate of Mr Murdoch, had made clear at a recent meeting with Mr Blair that The Sun and The Times would not support Labour at the next general election unless he promised a referendum. "A deal was done," the source said.

The Prime Minister's official spokesman said Mr Blair had not talked to Mr Murdoch recently about the issue but confirmed that he talked to Mr Stelzer on a regular basis, just as he spoke to many other figures in the media.

Michael Howard, the Conservative leader, said Mr Blair had "at last seen sense" on a referendum. He ridiculed the Prime Minister's declaration that he had no "reverse gear", saying: "Today we could hear the gears grinding as he came before us once again, lips quivering. Who will ever trust him again?"