Pope Francis has questioned US Republican presidential candidate Donald Trump’s Christianity over his call to build a border wall with Mexico.

Pope Francis said “a person who thinks only about building walls… and not of building bridges, is not Christian”.

The New York businessman supports deporting nearly 11 million undocumented immigrants.

He has alleged that Mexico sends “rapists” and criminals to the US.

Pope Francis made the comments at the end of trip to Mexico.

“A person who thinks only about building walls, wherever they may be, and not of building bridges, is not Christian. This is not the gospel,” he said.

He declined to say whether Americans should vote for Mr Trump, who is leading the Republican race for president.

“I say only that this man is not Christian if he has said things like that. We must see if he said things in that way and I will give him the benefit of the doubt,” the Pope said.