Outspoken Republican presidential candidate Donald Trump has hit back after having suffered a blow as the Pope questioned his religious credentials over his proposal to build a wall to keep Mexicans from migrating to the US.
The pontiff questioned Trump's faith after the billionaire said the way to deal with Mexican migration to the US was to build a wall on the border of the US and Mexico.
"A person who only thinks about building walls, wherever they may be, and not of building bridges, is not a Christian," Pope Francis said.
However, the Pope would not comment on whether or not he would hypothetically vote for Trump.
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Trump hit back saying that "for a religious leader to question a person's faith is disgraceful" and that the Pope "doesn’t see how Mexican leadership is outsmarting President Obama and our leadership in every aspect of negotiation".
Still, the comments come as a blow to Trump as he prepares for the next primary in South Carolina, which has a large Christian population.
That explains why Trump later stuck a conciliatory tone, saying: "I have a lot of respect for the Pope. He has a lot of personality and I think he's doing a very good job, he has a lot of energy."
Trump still leads heavily in the polls in South Carolina, with Marco Rubio, Ted Cruz and Jeb Bush trailing.
Meanwhile, on the Democrat side of the race senator Bernie Sanders has overtaken Hillary Clinton in the latest Fox News poll. Sanders now has 47 percent of primary voters nationally, up from 37 per cent in January, while Clinton has 44 per cent, down from 49 per cent a month ago.
However, an analysis of all polls still puts Clinton in front, but with a narrowing lead.