2017: David Cameron names the date for referendum on whether Britain should remain in the European Union David Cameron will today offer the public a simple "in or out" referendum by 2017 on whether Britain should remain in the European Union. In his much-delayed speech on Europe, the Prime Minister will promise that, if the Conservatives win the 2015 election, the public will have a straight choice between accepting the "new settlement" he will seek for the UK in the EU and leaving the 27-nation bloc altogether. His dramatic move will be welcomed by most Tory Eurosceptics. But pro-Europeans will worry that he is opening the EU exit door -and that Britain could lose job-creating foreign investment before the historic vote is held. Close allies insist that Mr Cameron believes passionately that Britain should stay in the EU and is confident of winning a better deal he can "sell" to the British people. They say the referendum would happen even if other EU leaders decide not to negotiate a new treaty to entrench reforms to the eurozone. Mr Cameron would still table demands to "repatriate" to the UK some EU powers - probably on employment, social issues, crime and policing. He is gambling that the threat of Britain withdrawing will extract concessions from other EU leaders. Mr Cameron will deliver what is widely seen as the most important speech of his premiership in London this morning, after postponing his plans to make it in Amsterdam last Friday because of the Algerian hostage crisis. He will rule out a referendum before the 2015 election, saying that would be a "false choice" because the shape of the new Europe is not yet clear. But he will announce that legislation will be drafted before the election and, if the Tories win, would be introduced immediately so a referendum would take place in the first half of the five-year parliament. The Prime Minister will declare: "It is time for the British people to have their say. It is time to settle this European question in British politics. Arguing that politicians can no longer duck the question, he will say that public disillusionment with the EU is at "an all-time high" in Britain and democratic consent for the Union is "wafer thin." In a jibe at Labour, he will say: "Those who refuse to contemplate consulting the British people would in my view make more likely our eventual exit." He will add: "Simply asking the British people to carry on accepting a European settlement over which they have had little choice is a path to ensuring that when the question is finally put - and at some stage it will have to be - it is much more likely that the British people will reject the EU." Mr Cameron will say: "That is why I am in favour of a referendum. I believe in confronting this issue - shaping it, leading the debate not simply hoping a difficult situation will go away. In an attempt to reassure pro-European businessmen worried about possible exit, he will say: "I believe something very deeply. That Britain's national interest is best served in a flexible, adaptable and open EU. And that such an EU is best with Britain in it. Over the coming weeks, months and years, I will not rest until this debate is won. For the future of my country. For the success of the EU. And for the prosperity of our peoples for generations to come. The Prime Minister will say: "With courage and conviction I believe we can deliver a more flexible, adaptable and open EU in which the interests and ambitions of all its members can be met. With courage and conviction I believe we can achieve a new settlement in which Britain can be comfortable and all our countries can thrive. Ed Miliband, the Labour leader, said last night: "The speech will define David Cameron as a weak prime minister, being driven by his party, not by the national economic interest."