Addressing a rally in South Carolina, Mr Trump responded to the Pope's comments about his Christianity.

"For a religious leader to question a person's faith is disgraceful. I am proud to be a Christian," Mr Trump said. "No leader, especially a religious leader, should have the right to question another man's religion or faith."

"[The pope] said negative things about me. Because the Mexican government convinced him that Trump is not a good guy," he said.