Republican presidential candidate Ben Carson says no Muslim should ever be elected president of the United States.
In an interview with NBC News broadcast on Sunday, Carson said Muslims are not suitable to become president, arguing their faith Islam - a religion professed by some 3 million Americans - is inconsistent with the US constitution.
"I would not advocate that we put a Muslim in charge of this nation," the retired neurosurgeon said. "I absolutely would not agree with that."
Asked whether the faith of a president should matter, Carson, a practicing Christian, said, "It depends on what that faith is."
"If it's inconsistent with the values and principles of America, then of course it should matter. But if it fits within the realm of America and consistent with the constitution, no problem," he stated.
The Council on American-Islamic Relations, the largest US Muslim civil rights and advocacy organization, condemned Carson over his controversial remarks.
"To me this really means he is not qualified to be president of the United States," said the organization's spokesman, Ibrahim Hooper. "You cannot hold these kinds of views and at the same time say you will represent all Americans, of all faiths and backgrounds."
Carson's comments came just two days after frontrunner Republican presidential candidate Donald Trump failed to respond to anti-Muslims remarks by a Trump supporter at a campaign rally.
The white man wrongly called US President Barack Obama a non-American Muslim and said Muslims are "a problem in this country."
Trump has responded to criticism, saying he was not obligated to correct the questioner.
In an interview on Sunday, Trump said that a Muslim in the White House is "something that could happen.
Asked whether he would be comfortable with a Muslim president of the US, Trump said, “Some people have said it already happened, frankly," in a clear reference to Obama. "But of course you won't agree with that."
A day earlier, however, the GOP frontrunner told CNN that he loves Muslims and that he would contemplate putting a Muslim in his cabinet.
"I love the Muslims. I think they're great people," the billionaire said after delivering a lecture to high school students in Urbandale, Iowa.