Republican Donald Trump appeared to raise questions about likely rival Hillary Clinton's religious faith at a closed-door meeting with evangelical leaders on Tuesday.

The presumptive GOP nominee, in a video clip of his remarks, appeared to suggest the public doesn't know "anything about Hillary in terms of religion."

"You know, she's been in public eye for years and years, and yet there's no, there's nothing out there. There's like nothing out there," he told the group.

"It's going to be an extension of Obama, but it's going to be worse because with Obama you had your guard up, with Hillary you don't. And it's going to be worse," he warned.

Donald Trump Mary Altaffer | AP

A spokeswoman for Trump's campaign did not immediately respond to a request for comment on exactly what Trump meant.

Trump's campaign on Tuesday also announced the formation of a new "Evangelical Executive Advisory Board" that will advise the candidate "on those issues important to Evangelicals and other people of faith in America," according to a release.

Members of the new group include former Minnesota Congresswoman Michele Bachmann, Liberty University President Jerry Falwell Jr. and Faith and Freedom Coalition leader Ralph Reed.

Footage of Trump speaking at the meeting at a Times Square hotel, which was closed to reporters, was posted by attendee Bishop E.W. Jackson on his Twitter feed.

Jackson told The Associated Press that Trump had been talking about the idea that conservatives are constantly scrutinized over their religion, how devout they are and their positions on social issues.

"He was saying in the context that liberals and the Democrats don't get those kinds of questions, they don't get their faith examined in that way," he said.

"He wasn't questioning her Christianity, but he was questioning the implications of her faith, compared to how conservatives tend to have their faith examined."

Clinton grew up in the Methodist church, attending church youth group and teaching Sunday school like her mother. While she doesn't often talk about her faith on the campaign trail, she occasionally quotes biblical verses and mentions her experiences in church.

"I am a person of faith. I am a Christian. I am a Methodist. I have been raised Methodist," she told voters in Iowa in January.

In the posted footage, Trump also takes issue with the idea of encouraging prayers for all leaders.

"I said: Well you can pray for your leaders, and I agree with that, pray for everyone. But what you really have to do is you have to pray to get everybody out to vote for one specific person," he said. "And we can't be again politically correct and say we pray for all of our leaders because all of your leaders are selling Christianity down the tubes, selling evangelicals down the tubes."

Trump has sometimes struggled to discuss religious issues. He has declined to cite his favorite biblical verse and toting around a photo from his confirmation as evidence of his Christian upbringing.

But in another video clip from Tuesday's event, Trump talked about the meaning of faith in his life.

"Christianity, I owe so much to it in so many ways, though life, through having incredible children, through so many other things," he said, noting his great support from religious voters in GOP primaries.

"The evangelical vote was mostly gotten by me," he said.

Trump also talked in another clip about the lack of "spirit" in inner cities.

"We've got to spiritize this country. And I'm not only talking about the inner cities. I'm talking about everywhere," he said, coining a new word.

Jackson, the bishop who posted video to Twitter, said that he'd walked into the meeting as more of an anti-Clinton voter than pro-Trump one, but said the meeting had changed his view.

"The thing I've heard most people say is, 'He moved the needle,'" he said. "People who came in with reservations, they have fewer reservations. Others left thinking, 'Maybe I need to take a look at him again.'"