The Staggers 3 July 2014 Labour's opposition to an EU referendum is its trump card with business Large companies are increasingly troubled by the threat of EU withdrawal under the Tories. EU flags float in Lille, northern France, on April 18, 2014. Photograph: Getty Images. Sign UpGet the New Statesman\'s Morning Call email. Sign-up The one moment of spontaneous applause during Ed Miliband's speech to business leaders today came when he declared: "I am absolutely convinced that our future lies in the EU". Further applause followed as he reaffirmed his opposition to an arbitrary in/out referendum (Miliband would only hold one in the unlikely event of a further transfer of powers to Brussels) and said "it is not the priority for the country". The EU is the one issue on which Labour has an unambiguous advantage over the Tories with business. Indeed, it is precisely this that troubles Len McCluskey (whose union has voted in favour of a referendum). He said yesterday: "As things stand, Labour won't [call for a referendum] because ducking this question is seen as part of Labour's commitment to business. That is a vast hostage to fortune. I would not like to be Ed Miliband explaining why he is not joining other parties in offering the British people a vote on something that is clearly a growing source of public concern." Many large companies are far more worried by the threat of withdrawal than they are by Miliband's proposed energy price freeze or the reintroduction of the 50p tax rate. Martin Sorrell recently revealed that he and others had told David Cameron that "if he were to drop the referendum he would be a shoo-in". That's almost certainly not the case (as Sorrell appeared to forget, most voters support a referendum) but it shows how desperate businesses are for Britain to remain in the EU. It is a point that Ed Balls, who has been troubled by the party's lack of industry support, is particularly keen to make. Having working hard to ensure that Labour did not rule out a referendum in all circumstances, he has swung firmly behind Miliband's position. After telling Newsnight that it would be "silly" to avoid a vote at all costs (a comment which was mistakenly thought to refer to a referendum at any time), he added: "We are not proposing a referendum now because we think to spend two or three years blighting investment and undermining our economy on the prospect of a referendum which David Cameron says he is going to have after he gets an unknown package of refoms would be bad for jobs and investment". Labour figures privately concede that they are still unlikely to win the support of a single FTSE 100 boss at the election, but the increasing possibility that the UK would leave the EU under the Tories may complicate the picture. It is, however, a price that Cameron is undoubtedly willing to pay. As has become ever clearer since his speech last year, had he not promised a referendum, he would likely now no longer be leader of the Conservative Party. › Leader: Labour should make itself the party of tax cuts and bold tax reform George Eaton is senior online editor of the New Statesman. Subscribe To stay on top of global affairs and enjoy even more international coverage subscribe for just £1 per month!