WATCH: Chris Christie says 'articulate' Cory Booker could be a formidable challenger to Trump

Former New Jersey Gov. Chris Christie on Friday said that Sen. Cory Booker (D-NJ) could be a formidable challenger to President Donald Trump because, among other things, he is "articulate."

"Cory Booker: Talented, smart, articulate," Christie said of Booker, who just hours earlier announced his run for the presidency in 2020. "I hope that he stays, in this campaign, to the roots that I saw him establish in New Jersey."

Christie, who was being interviewed at a Washington Post event by reporter Robert Costa, then went on to list Booker's credentials as a more moderate Democrat.

"He's somebody who was pro-voucher, he was pro-charter school, he is somebody who was tough on crime in his city of Newark," Christie said. "If he stays in that lane and is the articulate, inspirational guy that he is, then I think he's got a legitimate chance to be a serious potential problem for the president in a general election."

Watch the video below.