Repeating calls that he made earlier this week in the U.S., Trump told a British breakfast broadcaster that immigration would be the issue to sway the hotly-contested referendum towards a "leave" vote.

Never shy in coming forward, business magnate and Republican presidential candidate Donald Trump has told British TV viewers that he thinks the U.K. will vote to leave the European Union in June because of concerns over immigration.

"With the craziness that is going on with the migration, with people pouring in all over the place, I think that Britain will end up separating from the EU, that's my opinion," Trump said in the interview with ITV television program "Daybreak" broadcast on Thursday.

It's not the first time that Trump, who has made his anti-immigration stance a key part of his U.S. presidential nomination campaign, has made such comments. Earlier this week he told The Washington Post that he thought Britain "may leave the EU, yes, they're having a lot of problems."

"I don't want to make a comment about the U.K. leaving but I think they may leave based on - I'm there a lot, I have a lot of investments in the UK and I will tell you that I think they may leave based on everything I'm hearing."

Asked if he thought Britain would be better off if it left, he said: "I don't know, you'd have to ask them. I just think they may leave," the newspaper reported.

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