Donald Trump. John Moore/Getty Images

Independent presidential candidate Evan McMullin told Business Insider in a Wednesday interview that members of Republican nominee Donald Trump's campaign have told him that the Manhattan billionaire has times where he "hides in his apartment" and they're growing "frustrated."

Trump recently restructured his campaign, bringing on Breitbart News executive chairman Steve Bannon and pollster Kellyanne Conway to run it.

Previous campaign chair Paul Manafort stepped down last week after reports tied him to cash from pro-Russia entities in Ukraine.

McMullin said that it's "unclear" whether Trump "will make it through this campaign."

"He's taken some desperate measures with firing his campaign manager and hiring another one, wild swings in his policy positioning," he said. "I mean, he's desperate."

"I'm hearing from people inside his campaign that there are times now when he hides in his apartment and doesn't meet with any people," he continued. "When he campaigns he goes out to a place he has to fly back home to New York. This is a fragile man and a fragile campaign and I'm not quite sure what's going to happen in the days and weeks ahead of him. I'm not sure the [Republican National Committee] can continue to support him given his weakness as a man and as a politician and as a candidate for the presidency."

He added that his contacts within the Trump campaign, which he did not name, told him that they're "frustrated" with "the candidacy, with the organization, with Donald Trump's failure to stay on message."

Over the past week, Trump has read prepared speeches during his rallies, a switch from the free-wheeling style that he previously employed.

Business Insider reached out to Trump's campaign for comment, but they did not immediately respond.

McMullin recently decided to embark on an independent candidacy after being dissatisfied by Trump and Democratic nominee Hillary Clinton. He said that he's the only true conservative in the race. McMullin previously worked as a CIA operative and a policy director for the House Republican Conference.

Watch Business Insider's full interview with McMullin below: