When defending why he wasn't as productive as he promised his supporters he would be during his first 100 days, he told Fox News on Friday that the process of getting things done in Congress is "a very rough system. It's an archaic system ... It's really a bad thing for the country."

"Well, I think things generally tend to go a little bit slower than you'd like them to go," he said on "Face the Nation." "It's just a very, very bureaucratic system. I think the rules in Congress and, in particular, the rules in the Senate, are unbelievably archaic and slow-moving."

He also blamed Democrats for trying to block him from furthering his agenda. Republicans control both houses of Congress, but Democrats are able to filibuster legislation in the Senate, a tactic they used to slow the nomination of Justice Neil Gorsuch to the Supreme Court.

"All they do is obstruct," he told CBS. "All they do is delay. Even our Supreme Court justice, as you know -- who I think is going to be outstanding, Justice Gorsuch -- I think that it was disgraceful the way they handled that."

Trump's remarks come after he completed his first 100 days in office. Many important campaign promises that he said would be completed soon after he took office -- notably efforts to repeal and replace Obamacare -- have not yet been accomplished. It's unclear if other such legislative priorities, including tax reform and building a wall along the US-Mexico border, will get through Congress.