19/01/2015 11:16 GMT | Updated 19/01/2015 11:59 GMT

Cameron's EU Referendum Will Not Happen, Predicts Michael Portillo

British former politician Michael Portillo attends the ceremonial funeral of British former prime minister Margaret Thatcher in St Paul's Cathedral in central London on April 17, 2013. The funeral of Margaret Thatcher took place on April 17, with Queen Elizabeth II leading mourners from around the world in bidding farewell to one of Britain's most influential and divisive prime ministers. (AP Photo/Ben Stansall, Pool)

David Cameron's flagship pledge of a referendum on Britain's membership of the European Union after this May's general election is "not going to happen", former Conservative cabinet minister Michael Portillo has predicted.

The former defence secretary said that the prime minister would not be able to hold his EU referendum as the Conservatives would not win enough votes to gain a majority, in remarks that expose Conservative splits over Europe once again.

Speaking to comedian Matt Forde, Portillo said: "I don't foresee a majority Conservative government, and I don't foresee it because we don't have one at the moment and it's very unusual for there to be a swing to the party in office.

"I don't see how you get a referendum unless you have a majority Conservative government, I don't see how we can get a majority Conservative government I don't think it's going to happen, which is why I'm not having sleepless nights [about the referendum]."

Listen to Michael Portillo from 36.15 minutes in...

The former Tory minister accused Cameron of lacking a clear "rhetoric" to explain what he is doing in government, remarking: "I still find these people go up to me and say 'What is David Cameron about?'"

Cameron has staked his Eurosceptic credentials and his strategy to combat Ukip on the offer to reneegotiate Britain's position in Europe after May and putting that to voters in a referendum by 2017, with the Tories regularly insisting that only a Conservative government could ensure it happened. Any failure to deliver on promised EU reform will be politically dangerous for Cameron, who continues to be criticised for going back on a "cast iron guarantee" of a referendum on the Lisbon Treaty.

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Portillo also made the politically awkward disclosure that Cameron's Conservative ministers have told him "they can't do anything but sing Ukip's tune on immigration and Europe".

He discounted the idea that a Tory-Ukip coalition could still deliver Cameron's EU referendum pledge, suggesting that Ukip actually oppose a referendum as the party fears "it'll lead to a confirmation of Britain's place in the European Union".

Speaking to Forde in October in front of an audience in London, with a recording only published this week, Portillo warned that a vote to stay in the European Union could be "disastrous" as it would lead to a debate on whether Britain should join the Euro. said that he would vote to leave the European Union in the event of a referendum

"The consequence of a vote to stay in the European Union would be taken by the establishment as a sign that we had settled on our European destiny," he explained. "That would be disastorous as the whole thing about going into the euro would be reopened in a way that otherwise it could not possibly be."

Portillo previously has called for Britain to leave the European Union, writing in an op-ed for the Times that Cameron's EU reform plans were "virtually impossible".