President Trump intends to sign an executive order that would put at risk federal research funding to colleges and universities that fail to protect free speech on campus, he announced Saturday.

“Today I am proud to announce that I will be very soon signing an executive order requiring colleges and universities to support free speech if they want federal research dollars,” the president said during a speech at the Conservative Political Action Conference in Oxon Hill, Md.

“If they want our dollars, and we give it to them by the billions, they’ve got to allow people like Hayden and many other great young people and old people, to speak, free speech,” said Trump. “If they don’t, it will be very costly. That will be signed very soon.”

The specific details of Trump’s executive order are unknown.

The president’s announcement came after he brought on stage Hayden Williams, a conservative activist with Turning Point USA who was punched in the face Feb. 19 at the University of California, Berkeley.

Campus police on Saturday arrested Zachary Greenberg, who allegedly was behind the attack on Williams. Bail for Greenberg, 28, was set at $30,000.

Trump joked that Williams “could take a punch” and urged him to sue not only Greenberg “forever,” but also the University of California, Berkeley.

“He took a hard punch in the face for all of us, remember that,” Trump said. “He took a punch for all of us, and we can never allow that to happen. And in closing with Hayden, here is the good news: He is going to be a very wealthy young man.”