Ben Carson argued Wednesday that Donald Trump and Khizr Khan should apologize to one another to resolve their feud over the past week after Khan lambasted the Republican nominee in his speech at the Democratic National Convention.

Carson, an adviser to Trump, told CNN that the real estate mogul and Khan, the father of slain Army Capt. Humayan Khan, should end their conflict and move on, though he conceded it doesn’t seem likely that any apology will take place.