Former U.S. National Security Adviser John Bolton told the "Fox News Rundon" podcast Thursday that he believes President Trump’s senior adviser and son-in-law Jared Kushner is "the second-most powerful man" in the administration.

"I think he has enormous influence and access to the president," Bolton told host Jessica Rosenthal. "And I think it's been demonstrated in the foreign policy field, the domestic policy field, a whole host of things. Sentencing reform was a big priority, although the Republican Party was itself deeply divided over that. In addition to working on the Middle East peace plan -- 'the deal of the century,' as the president called it -- being involved in the China trade negotiations, the NAFTA negotiations.

"So, you know, he's been involved in a range of things that I don't think is equaled by anybody else in the president's roles of advisers or cabinet members," added Bolton, the author of the recently published "The Room Where It Happened," an account of his time in the administration.