WASHINGTON – Sen. Marco Rubio today on Fox News denied he was criticizing President Trump over North Korea but said he remained skeptical of any deal.

"The president is optimistic and he needs to be. He's the guy negotiating and he needs to make the other side feel like he's serious about getting something done," Rubio said. "But for the rest of us who are watching and know the history of North Korea, we should be skeptical. This is the county that has made promises before and has broken them."

Rubio said it was the job of lawmakers to be "clear-eyed" about any deal and that Congress should vote it, reflecting criticism of the Iran accord, so it's a "binding treaty."

Rubio was then shown a tweet of his that some interpreted as a knock on Trump, who said Kim Jong Un is a "talented guy." As a presidential candidate, Rubio mocked Trump for inheriting his father's wealth. "If he had not, right now, he would be selling watches in Times Square or be doing one of those infomercials that teaches you how to flip properties," Rubio said in 2016.

The Fox News host asked if he wanted to clarify that. "There's nothing to clarify," Rubio protested, noting Trump was elected and will be judged by voters again, unlike Kim. "Their government is a cult … It's a very strange and weird place. It is what it is and I'm not going to ignore that reality."

Rubio also gave measured treatment to the "unusual" video the Trump administration produced for the summit in Singapore.