Jean-Claude Juncker could force Britain out of EU

David Cameron has reportedly warned that Britain could leave the EU if Luxembourg ex-prime minister Jean-Claude Juncker becomes the next president of the European Commission.

Centre-right European People's Party's (EPP) choice to head the European Commission, Jean-Claude Juncker. Picture: Getty

German news magazine Der Spiegel claims the Prime Minister issued the warning to German Chancellor Angela Merkel at the EU leaders’ summit in Brussels on Tuesday.

Quoting sources close to those at the summit, the magazine said Mr Cameron fears the appointment of continuity candidate Mr Juncker would destabilise the UK government to such an extent that it would bring forward an in-out EU referendum.

Mr Cameron reportedly added: “A figure from the Eighties cannot resolve the problems of the next five years.”

Mr Juncker yesterday appeared to hit back at Mr Cameron, insisting European leaders should not be “blackmailed” into rejecting his presidential bid.

The politician told Germany’s Bild am Sonntag newspaper he now has support from “a broad majority” of conservative and centre-left leaders and was confident of securing the job.

A Downing Street spokesman said: “We are not commenting on this. It was a private meeting, a private conversation.”

Mr Cameron has previously made it clear he views the former Luxembourg leader as a symbol of Europe’s past and has argued that a reformer should take charge of the EU executive to pave the way for change.

However, on Friday Ms Merkel gave her backing to Mr Juncker for the key post, putting her and the Prime Minister on a collision course.

Both Mrs Merkel and Mr Juncker’s parties are members of the European People’s party (EPP) bloc, which still dominates the parliament and has selected him as its preferred candidate.

Iain Duncan Smith said Mr Cameron knows he must deliver “significant return of powers” from the EU to win the support of Tory colleagues in a referendum on British membership.

The Work and Pensions Secretary said the Prime Minister was clear he could not “come back with nothing” from a mooted renegotiation after the general election.

Although Mr Duncan Smith stressed he was “happy” with the premier’s stance, the comments will heap pressure on Mr Cameron to flesh out his ambitions for repatriating powers from Brussels.

Mr Duncan Smith said: “I think you will find that the Prime Minister in due course will be a little clearer about some of the stuff that he thinks.

“The key thing is he knows very well that he can’t come back with nothing. I don’t think the Prime Minister in any way is lost on that fact that he will need to get back some substantial and significant return of powers. It is for him to deliver that.”

Mr Duncan Smith called for new rules to limit migration from the EU, and said Brussels should be stripped of control over who is entitled to state benefits in Britain.

He said he challenged Mr Cameron face-to-face to confirm his commitment to delivering a referendum after the next election.

“I have looked him in the eye and I have asked him the simple question: you are absolutely clear this referendum is going to happen if the Conservatives are back in power and he said ‘Yeah, I won’t be in a government if they won’t have a referendum.’”

Speaking on the by-election campaign trail in Newark, he signalled that if Mr Cameron failed to get a good deal, he would be ready to vote to leave the EU as Britain could “prosper” outside the union.