Blair plans an all-party alliance to win yes vote

Tony Blair will form an all-party campaign with the Liberal Democrats and pro-European Tories in an attempt to win a referendum on the European Union constitution that he will announce in a Commons statement today.

Tony Blair will form an all-party campaign with the Liberal Democrats and pro-European Tories in an attempt to win a referendum on the European Union constitution that he will announce in a Commons statement today.

The Prime Minister will confirm he is to adopt the high-risk strategy of calling a referendum. But his gamble has alarmed some Europhiles, who fear the vote could easily be lost, setting back the European cause and scuppering hopes that Britain will join the euro. Mr Blair will try to allay such fears by enlisting the support of Charles Kennedy, the Liberal Democrat leader, and prominent Tories such as Kenneth Clarke, the former Chancellor. He believes such a common front would isolate the Tories, who will head the no campaign in the referendum, and put them under pressure to say how they would "renegotiate" the terms of Britain's membership of the EU.

Although the British public would be asked in the referendum whether they support the constitution, the Prime Minister will campaign on whether Britain should be a "key player" in the EU in an attempt to turn the plebiscite into a vote on Britain's continued membership.

Today's confirmation of his astonishing U-turn will fail to satisfy the Tories, who have long argued for a referendum on the new EU blueprint due to be approved by EU leaders in June. Michael Howard, the Tory leader, will call for the vote to take place this year but Mr Blair will make clear that it is unlikely to take place until after the general election he has pencilled in for May next year.

The Prime Minister believes Parliament must debate the new EU constitution before it is put to the people. The new treaty will not be written until October or November, leaving little time to push through the necessary legislation before a May 2005 election.

But Mr Howard said last night that Britain should "move quickly to hold a referendum" as soon as the EU approves the document. "There is no case for delaying any further and there is no point in MPs wasting months talking about the constitution if it is going to be completely unacceptable to the British people," he said.

The Tory leader warned: "The Prime Minister plans to try to scare the British people with the threat that if we don't accept this constitution, then we have no option but to leave the EU. That is simply not the case." In a foretaste of today's Commons clash, the two leaders crossed swords yesterday when Mr Blair made a statement on his talks with President George Bush last week.

Mr Howard welcomed the Prime Minister's "big U-turn" but said that, under the proposed constitution, Europe would represent Britain in such discussions with the US. Dismissing Mr Howard's remarks as "absolute nonsense", Mr Blair said: "There is nothing to prevent us taking a view as an independent sovereign country. It will be a pleasure to debate the reality, not the myth."

Mr Kennedy, who supports a referendum, has been sounded out about an all-party campaign and will join it. But last night he criticised Mr Blair's handling of the issue. The Liberal Democrat leader said: "The way it is being announced is amateurish and clumsy. One minute the Foreign Secretary is scheduled to tell Parliament; the next it's the Prime Minister.

"Nods and winks to selected reporters and newspapers are not the way to tell the country about a matter of such importance. The campaign itself will have to be run with more confidence and clarity than this."

Keith Vaz, Labour's former minister for Europe, opposed a referendum but said the Prime Minister could win. "What he will need to do is take the lead, go up and down the country campaigning. I am very convinced he will win the referendum."