An anti-euro protester stands outsides Westminster

If the UK had an "in-out" referendum tomorrow on membership within the EU half the country would vote "out", a majority that would comfortably pass the motion.

A study commissioned by Guardian/ICM suggests that 70 per cent would like to have a vote on their membership with 49 per cent voting for an EU departure, and 40% requesting to stay in - exactly the same percentage of Britain exports to the Eurozone.

The figures were released prior to a Commons vote on where MPs were expected to toe the party line and to vote against a referendum.

There is a clear majority for staging a referendum on Britain's relationship with Europe in each of the social classes and across the regions and nations of the UK. Men and women are similarly keen, as are supporters of all three main parties, although rather more Conservative (71 per cent ) than Labour voters (65 per cent ) are calling for a poll. Overall, just 23 per cent of all voters say they would be against a vote that "could ask the public whether the UK should remain in the EU or pull out instead".

Earlier David Cameron h issued a final appeal to his MPs not to rebel in a vote on a referendum on the UK's membership of the European Union.

All Conservative MPs, and Lib Dem and Labour MPs, were instructed to vote against the motion but nearly 70 Tory MPs are likely to defy the party whip.

Mr Cameron, facing the biggest rebellion of his premiership, told them the approach and the timing was wrong.

"The time for reform is coming," he said ahead of the debate.

The motion calls for a referendum on whether the UK should stay in the EU, leave the EU or renegotiate its membership.