President Trump Donald John TrumpBiden on Trump's refusal to commit to peaceful transfer of power: 'What country are we in?' Romney: 'Unthinkable and unacceptable' to not commit to peaceful transition of power Two Louisville police officers shot amid Breonna Taylor grand jury protests MORE on Wednesday warned members of the anti-fascist movement, commonly referred to as "antifa," that opposition to them could be "tougher" and "much more violent" if their critics decide to "mobilize."

"They better hope that the opposition to antifa decides not to mobilize,” Trump told the conservative outlet The Daily Caller in an interview. "Because if they do, they’re much tougher. Much stronger. Potentially much more violent."

ADVERTISEMENT

"And antifa’s going to be in big trouble," the president continued. "But so far they haven’t done that and that’s a good thing."

The left-wing antifa movement is known for its direct protests of events and figures that supporters accuse of spreading white supremacist and fascist ideals.

The loosely-affiliated network of groups have participated in public protests of multiple Trump administration and GOP figures. Critics have slammed its members for inciting violence at events they organize and attend.

Trump during the interview Wednesday said the groups that oppose antifa include "the military," "the police" and a lot of "tough people."

An anti-fascist group in Washington, D.C., last week protested outside the home of Fox News's Tucker Carlson, whom they accused of promoting white nationalism from a mainstream platform.

D.C. police are investigating an offense of defacing public property after one demonstrator spray-painted an anarchist symbol on Carlson's driveway, CBS News reported.

Carlson is a co-founder of The Daily Caller, the outlet that conducted the interview with Trump on Wednesday.

Antifa groups describe the use of violence as necessary to combat authoritarianism. They have participated in brawls with right-wing groups across the country, including the white nationalist demonstrators during the deadly rally in Charlottesville, Va., last year.

The Anti-Defamation League describes the antifa ideology as "rooted in the assumption that the Nazi party would never have been able to come to power in Germany if people had more aggressively fought them in the streets in the 1920s and 30s."