DAVID Cameron has urged voters who want to preserve the United Kingdom to vote to stay in the European Union in his strongest display to date of playing the Union card during the in-out referendum campaign.

The Prime Minister's comment came as he was challenged by the SNP’s Pete Wishart, who complained that the Tory leader had put Scotland's relationship with the EU at risk by calling the national vote on the UK's membership in the June 23 referendum.

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During a lengthy grilling of the PM by the cross-party House of Commons Liaison Committee, Mr Wishart suggested Scottish voters would have "every right" to demand a second independence referendum if the result of the UK-wide vote was to take them out of the EU against their will.

He suggested Scottish voters had been "misled" by the argument used by the No campaign during the 2014 referendum that Scotland's membership of the EU would be at risk if it voted to leave the UK. With the whole country's EU membership now in question, that argument now looked "tenuous", claimed the Perth MP.

The Herald:

But Mr Cameron insisted the decision on EU membership was for the UK as a whole and that all parts of the UK should accept the outcome.

"My position is that this is a United Kingdom decision. We make it as one United Kingdom, we accept the result whatever it is," declared the PM.

But he then alluded to the possibility of a second independence poll by stressing: "I would argue to anyone in the United Kingdom who cares as passionately as I do about keeping the United Kingdom together that the safe and sensible choice is to vote to stay in a reformed European Union."

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Yet Mr Wishart pressed the point about Scotland being “forced out of the EU against its collective national will".

He told the PM: "Your message to the people of Scotland is that if we are taken out against our national will, we've just somehow got to lump it and get on with it and maybe even thank us for taking us to this point. You have put us to risk with this; you could possibly be ending our relationship with the EU."

Mr Cameron pointed out how opinion polls taken before the referendum was called found "remarkably little difference" between Scotland, England, Wales and Northern Ireland in terms of whether people thought EU membership should be put to a vote.

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"The opinion polls were pretty clear. The Scottish people wanted a referendum and that's what we are having," he told the committee.

"The message is that we are safer, stronger and better off in but we are one United Kingdom and we take decisions about joining international organisations as one United Kingdom," added the PM.