Ben Carson will not be in Donald Trump's administration, according to his longtime confidant Armstrong Williams. | AP Photo Carson won't serve in Trump administration, aide says

Ben Carson will not serve in the Trump administration, according to a longtime confidant of the retired neurosurgeon.

“He has no interest in a cabinet position, or any position in the administration,” Carson adviser Armstrong Williams told POLITICO.

Carson has been frequently mentioned as a possible Health and Human Services or Education secretary. But Williams said Carson believes he can better serve President-elect Donald Trump as an outside adviser, given Carson's lack of governing experience.

“It’s not an issue of him turning down anything,” Williams said. “It was clear that he had his pick of what he wanted to do.”

Carson ran for the 2016 Republican nomination after becoming a conservative icon for his harsh criticism of Obamacare. After dropping out of the race, Carson became an enthusiastic supporter of Trump.