President-elect Joe Biden addressed the country after supporters of President Donald Trump swarmed Capitol Hill on Wednesday to protest the results of the presidential election.

“At this hour, our democracy is under unprecedented assault, unlike anything we’ve seen in modern times. An assault on the citadel of liberty, the Capitol itself,” Biden said.

Biden stressed during his speech that the “words of a president matter,” and called President Donald Trump to go on national television to condemn the violence.

“I call on President Trump to go on national television now to fulfill his oath and defend the Constitution and demand an end to this siege,” Biden said during a speech in Wilmington, Deleware.

Biden repeatedly stressed the historical nature of the images coming from Capitol Hill as Trump’s supporters swarmed into the House and Senate chambers, disrupting the proceedings to certify the electoral college vote.

“This is not dissent, it’s disorder. It’s chaos. It borders on sedition and it must end now,” he said. “I call on this mob to pull back and allow the work of democracy to go forward.”

He urged all American leaders to stand up and condemn the violence that threatened elected officials.

“This god-awful display today is bringing home to every Republican, Democrat, and Independent in the nation that we must step up,” he said. “This is the United States of America.”

Biden blamed a “small group of extremists” for the violence and called for it to end.

“Let me be very clear. The scenes of chaos at the capitol do not reflect a true America. Do not represent who we are,” he said.

Biden said he was “genuinely shocked and saddened” that the country had come to a “dark moment” in its history.

He said he remained optimistic about the future of the country and would work to heal the country.

“The work of the moment and the work of the next four years must be the restoration of democracy, of decency, honor, respect, the rule of law,” he said.