Referendum calls add to euro pressure on Cameron

Mr Cameron said he would have “no hesitation” in wielding Britain’s veto to block an European Union treaty change to resolve the eurozone crisis if it did not meet UK requirements.

However the efforts from Downing Street to insist a referendum was not necessary are struggling, with the leader of Mr Cameron’s Tory MEPs, Martin Callanan, joining in the chorus calling for one.

Mr Callanan followed fellow senior Tories Boris Johnson and Northern Ireland Secretary Owen Paterson, in demanding the return of powers from Brussels to Westminster as the price for acquiescence in a treaty, and to put any deal to the British people in a referendum.

A Downing Street spokesman said a public vote was not needed as proposed changes will not transfer powers to Brussels, and Mr Cameron has said he will ensure that any treaty includes safeguards to protect the City of London from European regulation.

Mr Cameron spoke briefly as he went into the start of what could turn out to be marathon negotiations in Brussels – the eighth EU summit on the eurozone crisis this year – saying the talks were important. “It’s good for Europe and good for Britain. We’ve got to protect British interests and that’s what we will be discussing.”

His first meeting before a dinner with all 26 other EU leaders was due to be a private conversation with Italian Prime Minister Mario Monti .

Labour leader Ed Miliband said Mr Cameron seemed “incredibly weak because he’s leading a divided Government and a divided party”.

He said: “First of all, saying it was nothing to do with him; then saying he was going to bring back powers to Britain and use treaty change to win back powers from Brussels; then conceding that wasn’t going to happen; then threatening a veto and, I think, most of his European partners seem to be shrugging their shoulders and saying ‘Well, look, he’s not interested in positively engaging to get a good outcome here, he’s interested in just shouting from the sidelines and trying to satisfy his own backbenchers.”