Portillo has supported Brexit, though also has expressed the opinion that in the British system, where Parliament is sovereign, the 2016 Brexit referendum "absolutely does not fit with our system" and that "parliament has the right to interpret" the result. In a 2016 television discussion he said that "because of the catastrophic blunder committed by David Cameron, [Nigel] Farage deserves a place in history" because "he spooked the Prime Minister into holding a referendum that he then lost." He also condemned Theresa May's 2018 "Chequers plan" for exit negotiations as "the most dreadful betrayal, and if I had been a member of the Cabinet, I would have been one of the ones who would have quit over the weekend." On another occasion Portillo exclaimed (as a pundit on "This Week") that "short of marching Mrs. May into a railway carriage in the Compiègne forest, they could not have produced a more humiliating surrender."