Britain's EU membership renegotiation would be 'a monumental error of statesmanship', says Blair

Tony Blair: 'You need the heft of the EU' (PA)

Plans to renegotiate the terms of Britain’s membership of the European Union by David Cameron could result in it leaving the 27-nation bloc, Tony Blair warned today.

The former Prime Minister said it would be “a monumental error of statesmanship” for the UK to turn its back on Europe. He said the Conservatives had caught a “virus” on EU withdrawal, and suggested that Mr Cameron would be pushed down the exit route even though he supports continued membership.

In a speech to be delivered in the next weeks, Mr Cameron is expected to say that a “new settlement” between Britain and the EU could be put to a referendum after the 2015 election. But Mr Blair argued that renegotiation “is the refuge of those who want to leave but want to persuade people that it’s really just an adjustment of our relationship”.

He told the Business for New Europe group at a speech in London: “Then in the course of the adjustment, when the going gets very rough – as it will – they will then say, ‘well, it’s a pity but now it seems adjustment is not enough’. Don’t go down this path unless we are prepared to follow it all the way.”

Although Mr Blair failed to become the first President of the European Council, the group comprising the EU’s 27 national leaders including Mr Cameron, allies say he is keen to succeed Herman Van Rompuy in the post when his term of office ends in 2014. But some Brussels insiders believe Britain’s semi-detached status – and Mr Blair’s backing for the US invasion of Iraq in 2003 – may count against him.

Today Mr Blair admitted that much of the criticism levelled at the EU was justified, but insisted that it was dangerous for Britain to edge towards the exit. He argued that despite the eurozone crisis, the case for the EU is stronger today than when the project began 66 years ago. Then the rationale was peace after the Second World War. Today, he said, the reason is not idealism but to leverage power in a “new world” in which economic might is shifting to China and India.

“You need the heft of the EU,” he said. “We need the EU to help pursue our national interest. With it, we count for more. Without it, we count for less.”

Insisting that it is not “sensible” to be talking about a referendum now, Mr Blair suggested some Tories have developed an irrational fixation on withdrawal. “The right have got it really bad on this Europe thing and it is a kind of virus that makes you want to take positions for the sake of asserting them, when a rational analysis says you don’t need to be in that position,” he said.

Mr Blair admitted that Britain could have a future outside the EU with its own “unique brand”, but said it was a “delusion” that it could be like Norway or Switzerland. The UK would lose its global leadership role, he argued, relegating itself in the league of nations; it would be outside the decision-making process of the single market and it would lose the ability to co-operate on issues such as climate change, trade talks and foreign policy.