President Donald Trump's newest national security advisor, Robert O'Brien, explained on Sunday that his job does not include saying no to his boss.

Following the apparent death of ISIS leader Abu Bakr al-Baghdadi, O'Brien spoke to NBC's Chuck Todd about the operation.

"Are you comfortable to say no to him?" Todd asked.

"Look, it's not my job to say no to him," O'Brien replied.

Todd was taken aback: "You believe it's not your..."

"I wasn't elected president," O'Brien interrupted. "It's my job to make sure he gets the very best options and advice from his cabinet secretaries and advisers. It's my job to give him my best advice."

Over the weekend, the White House press secretary described Trump as a genius who is smarter than his staff.