DAVID Cameron has claimed the Vote Leave campaign is "losing the argument" in the EU referendum campaign after Nigel Farage reportedly suggested that if the June 23 vote were a narrow victory for Remain, the Out camp would campaign for another vote.

The Prime Minister, in an unscripted speech at the Mansion House in the City of London, said: "When people start arguing for a second referendum, before they have even had the first one, that really demonstrates they are losing the argument. The Leave campaign are losing the argument, particularly this economic argument.

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"One minute they want to be like Norway, the next minute they want to be like Canada, then they want to be like Albania. I don't think they have really got a thought-through argument about Britain's economy."

Mr Cameron, perhaps with one eye to Nicola Sturgeon in Scotland, insisted he believed referendums were a "once in a lifetime, once in a generation opportunity...You can't have neverendums, you have referendums," he declared.

The PM went through nine "myths" he claimed were put forward by the Brexit campaign such as Britain would thrive outwith the single market, that it would be easy to create new trade deals and that there was an equal weight of economic analysis arguing for both sides of the In-Out argument.

Insisting he was making a practical "Britain First" argument, Mr Cameron told a gathering of business leaders that it was clear from all of Britain's friends across the globe to the world's leading economic authorities such as the IMF, World Bank and OECD, that they all believed it was best for Britain to stay in the EU.

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The Tory leader made clear that, while there were frustrations with the institution of the EU, leaving the 28-member bloc would "wreck our economy" and that the UK with its "special status" was much better off and could thrive within the EU.

Asked if there was too much scaremongering, Mr Cameron insisted he was making an "absolutely positive argument" for Britain to remain in the EU but that it was also right to point out the "big economic dangers" of leaving.

Asked about fears of increased terrorism from the deal with Turkey, the PM pointed to the warnings from Britain's intelligence chiefs that it was in the UK's security interests to remain a part of the Brussels bloc.

"This is a time for strength in numbers, for sticking with our friends and allies rather than breaking apart," he stressed.

Mr Cameron's words followed earlier remarks from the Ukip leader.

Noting how a narrow victory for the remain campaign would cause "resentment" in sections of the Conservative Party, Mr Farage tried to play down claims he would campaign for a second vote if there were a close result at the polls next month, insisting he felt Britain would still opt to leave the EU.

His comments came after he was quoted by the Daily Mirror as saying a tight vote to stay in Europe would leave "unfinished business".

He told BBC Breakfast: "I believe we're going to win this referendum, why? Because there's far more passion on the leave side of the argument. Leave voters are much more likely on June 23 to go down to their local primary school and vote, so I we are going to win.

"If we were to lose narrowly, then what I can see is a large section - particularly in the Conservative Party - who feel the Prime Minister is not playing fair, that the remain side is using way more money than the leave side and there would be a resentment that will build up if that were to be the result."

Mr Farage is scheduled to appear opposite David Cameron on an ITV debate ahead of the vote next month, a decision which was condemned by the Vote Leave camp as a "stitch up".

The latest poll by the Daily Telegraph has suggested the weight of public opinion is behind remaining in the EU, with 51 per cent of people wanting to stay, while 45 per cent would vote to leave - a one per cent drop since their last poll in April.
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The long-time Eurosceptic denied that his suggestion he would fight for a second referendum would only serve to further stoke tensions in the Leave campaign.

He said: "I'm not putting it on the agenda; I don't want a second referendum' I want to win this one."