IT may be nearly five years away, but pro and anti-Europeans were today already squaring up for the possibility of an in-out referendum on Britain’s membership of the EU.

Prime Minister David Cameron today promised the referendum by the end of 2017 if the Conservatives win the next general election.

In a major speech in London, Mr Cameron said that the Conservative manifesto for the 2015 general election will ask for a mandate to negotiate a “new settlement” for Britain in Europe, which will be put to voters in a referendum within the first half of the five-year Parliament.

But the Prime Minister said he will campaign “with all my heart and soul” for Britain to stay in the European Union when the referendum comes.

And he warned voters that if the UK did decide to leave, it would be “a one-way ticket, not a return”.

Speaking to a business audience in the City of London, Mr Cameron called for a new EU treaty to reshape the 27-nation bloc, resolve the problems of the eurozone, allow the transfer of powers back from Brussels to national governments and make Europe’s economy more competitive and its institutions more flexible and democratically accountable.

Mr Cameron said it was his “strong preference” to enact these changes for the whole EU, not just Britain alone.

But if other member states are unwilling to go ahead with a new treaty, Mr Cameron said he was ready to renegotiate the UK’s position to achieve a settlement “in which Britain can be more comfortable and all our countries can thrive.”

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