President Donald Trump's longtime friend and billionaire backer Tom Barrack is "shocked" and "stunned" by some of the president's rhetoric, he told The Washington Post.

The Colony Capital CEO, who informally advises Trump after heading his inaugural committee, said he tells Trump "all the time" that he doesn't "like the rhetoric," the newspaper reported. Barrack described his relationship with Trump as one in which he can disagree while remaining a loyal confidante.

The real estate investor told the Post that he particularly disagreed with Trump's plays to his so-called base, like his push to restrict immigration from several Muslim-majority countries and build a physical wall on the U.S.-Mexico border.

"He thinks he has to be loyal to his base," Barrack told the newspaper. "I keep on saying, 'But who is your base? You don't have a natural base. Your base now is the world and America, so you have all these constituencies; show them who you really are.' In my opinion, he's better than this."

Barrack, who has business connections in Qatar, also urged Trump not to get involved in a dispute among Persian Gulf nations after the president referred to Qatar as a high-level funder of terrorism.

Read the full Post report here.