David Cameron: 'The Lisbon treaty is effectively a constitution for Europe'
Leader David Cameron has played down suggestions of a rift over Conservative policy towards an EU Treaty referendum.
Mr Cameron has promised a referendum if his party wins power before the treaty is ratified by all 27 EU states.
But Ireland's "yes" vote means he is under pressure to say what he would do if it is in force before the election.
Mr Cameron also rejected talk of splits with Boris Johnson, who says British people should be "consulted" on parts of the treaty even if it is ratified.
The issue threatens to dominate the first day of the Conservative Party conference in Manchester, where Mr Cameron and senior ministers have been setting out plans to reform welfare policy.
Mr Johnson told the BBC it was "bizarre" that people had no say about the prospect of former prime minister Tony Blair becoming president of the EU - a move made possible because the treaty, which aims to streamline decision making in an enlarged EU, creates a President of the European Council.
The London mayor said he believed there should be "a consultation as soon as possible" but admitted that if it was ratified by the Czech Republic and Poland then it would be "a different situation".
But if the treaty was in force by the time of the next general election - expected next spring - he said: "It's certainly the case that you could put key parts of this treaty to the people and you could certainly find out what people thought about it."
Mr Cameron told the BBC that he and Mr Johnson "agree entirely" on the party's policy on Europe adding saying "we want to have this referendum" on the treaty.
I think that would be pointless - that would be creating a drama unnecessarily
"Boris wants that referendum. I want that referendum. The British people want that referendum. They've seen the Irish vote twice and we haven't been able to vote once," he said.
"What we're saying is as long as this treaty is being debated or looked at anywhere in Europe we can hold that referendum. That's what Boris thinks, that's what I think."
Mr Cameron has not committed to a referendum if the treaty has been ratified - he says he does not want to prejudice decisions in other countries that have yet to ratify the treaty. He has said only that the Conservatives "would not let matters rest".
The ratification process is being held up by Poland - which is expected to sign within days - and a legal challenge in the Czech Republic.
In his speech to the Conservative Party conference in Manchester, shadow foreign secretary William Hague said the Tories were "right" to call for a referendum on the treaty and right to "stick with" this commitment.
He said the "explicit consent" of the British people was needed for such a major change in the UK's relationship with Europe.
But the former foreign secretary Sir Malcolm Rifkind said it did not "make sense" to hold a post-ratification referendum.
A lot of important Tory supporters aren't happy
Nigel Farage UKIP leader
He told BBC Radio 4's World at One: "It ceases to be a referendum and becomes an opinion poll. We would win that referendum, no doubt about that, but what do you then do?
"I think that would be pointless - that would be creating a drama unnecessarily."
Shadow business secretary Ken Clarke - one of his party's best known euro-enthusiasts - told a fringe meeting he was "wholly content" with the "settled" Conservative line on the treaty.
He added: "I do not think it would be remotely sensible to seek to change that policy in the course of this conference and I know for a fact that with my complete approval, it will not be changed during this conference."
And shadow home secretary Chris Grayling said there was "a very strong sense ... that we simply can not accept what is on the table" with the Lisbon Treaty.
But he urged the party not to become obsessed with Europe in the run-up to a general election "when the rest of the country want to be debating health and education and how we are going to balance the books".
UK Independence Party leader Nigel Farage said some Tories were preparing to defect to them if Mr Cameron failed to deliver a referendum if the Conservatives win power.
"A lot of important Tory supporters aren't happy," he said.
"And they're making that obvious by the overtures they are making to the UK Independence Party, telling us that Conservatives no longer represent them."
In a letter to Mr Hague, Foreign Secretary David Miliband said: "To be credible in the eyes of British people you need to answer the simple question of what you now plan to do following the failure of your campaign against the Lisbon Treaty."
He added: "Isn't it really the case that the old obsessions and divisions in the Conservative Party have not been addressed, and that the issue of Europe shows that your party only promises a repeat of the dysfunction that marred the Major government?"
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