Abstain in EU vote, Tory ministers advised 12 May 2013 Last updated at 05:08 Tory ministers are being advised to abstain in a Commons vote on the failure to introduce laws guaranteeing a referendum on the UK's EU membership, a Downing Street source has confirmed. It is thought about 100 backbench MPs could oppose government policy. Number 10 said David Cameron, who wants a referendum to take place by 2017, was "relaxed" about the situation. Labour is expected to oppose the motion and has accused the prime minister of being scared to confront his party. The Speaker of the House of Commons, John Bercow, has yet to decide whether to select for debate an amendment "regretting" that there were no plans for an EU referendum bill in the Queen's Speech. But if there is a vote on Wednesday, ministers will, in the words of a senior source, be "guided" to abstain, says BBC political correspondent Ross Hawkins. Other MPs, including ministers' parliamentary aides, will be free to vote with their consciences, said our correspondent. One of them - Gavin Barwell, parliamentary private secretary to Education Secretary Michael Gove - has already said that he intends to support the amendment. Wrong sign Mr Cameron has promised a referendum if the Tories win the next general election. The prime minister has said the pledge to hold an in/out vote by 2017, once he has negotiated the return of some powers from Brussels, will be in the next Conservative manifesto. He has told the rebels he cannot introduce a bill paving the way for this because of opposition from his Liberal Democrat coalition partners. But Conservative unrest over Europe has gained fresh momentum following the recent election success of the UK Independence Party and comments by Tory grandees such as Lord Lawson suggesting EU withdrawal. Eurosceptic backbenchers, led by Basildon and Billericay MP John Baron, want legislation in the current Parliament binding the next government to hold a referendum. However, it would stand little chance of being passed as Labour and Liberal Democrat MPs, most of whom oppose a referendum on those terms, as well as many Conservatives, would vote against it. Speaking to the Labour group Progress on Saturday, Labour leader Ed Miliband said the prime minister was "hiding behind the sofa" too scared to confront his party. Mr Miliband said: "It is wrong now to commit to an in/out referendum and have four years of uncertainty and a 'closed for business' sign above our country." Labour aides stressed that Mr Miliband was opposing the decision to signal a referendum now but not ruling out the possibility of a referendum in the future.