Ben Carson is advising Donald Trump on the list of potential Supreme Court nominees the GOP frontrunner says he would put forward as president, Carson told the Washington Post.

Trump has said he plans to release during the campaign a list 10 to 12 people he would possibly nominate for the Supreme Court. Carson told the Post that he and Trump went through the list over the phone Tuesday.

“We now talk from time to time, including today, and we went over his list, which I think would be extraordinary,” Carson said. “He’s got his team studying these people very carefully.”