Europe needs swagger

Alastair Campbell: Irish must help reject Brexit

Alastair Campbell, political aide to former U.K. Prime Minister Tony Blair, remains positive about the prospect of Britain remaining in the European Union, telling CNBC he believes people will "make the right decision" and vote to stay in.

"The longer this campaign has gone on, the more I think that's what's happening is that…lots and lots and lots of people in the middle really are genuinely confused and they are no longer listening that much to politicians or to the media," he said on Thursday.

"I think they're going to be persuaded…by each other," he added.

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On June 23, the U.K. decides in a referendum if it want to remain a member of the 28-country bloc, or leave – a choice which has come to be known as Brexit. Campbell, best known for his role as Blair's spokesman and press secretary, also advised the Better Together campaign against independence for Scotland.

"Most of our media, particularly our newspapers, don't want people to know the truth about the European Union," Campbell said.

"I understand why people might not like David Cameron and might not like the European Union, but we've got to move beyond that and try to engage in the really, really serious arguments about trade, about business, about environmental protection, about where power lies. And be honest about that: that Britain would become a much less powerful country. "

Speaking from Dublin where he was addressing a conference about Brexit, Campbell said there were 660,000 Southern Irish-born people living in Britain who will be entitled to vote plus 1.5 million who have varying degrees of "Irish blood and identity".

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"You meet very few people here who think it is anything other than a very bad idea for the U.K. to leave the European Union." He cited concerns about investment, energy policies, customs and tariffs.

He said many Irish business people feel impotent in the debate, but planned to urge them to influence friends and family who do have a say in the matter.

"I think the Irish can have a big impact upon the Irish population in the U.K., he said.

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