U.S. Speaker of the House Nancy Pelosi on Thursday called on Vice President Mike Pence to immediately remove President Donald Trump from office, one day after the president incited rioting inside the U.S. Capitol.

Pelosi, currently the most powerful woman in Congress, said she joined Senate Minority Leader Chuck Schumer in calling Pence to invoke the 25th Amendment, which allows the president to be removed and for the vice president to ascend to the presidency.

“If the vice president or Cabinet do not act, the Congress may be prepared to move forward with impeachment,” she told reporters.

The 25th Amendment, passed by Congress in 1965 and ratified in 1967, provides the framework for the vice president to become president if the president is unable “to discharge the powers and duties of his office,” language that does not consider anyone aside from a man becoming president.

The process involves the vice president and the president’s Cabinet alerting congressional leadership that the president is unable to do their job. The amendment has never been invoked to permanently remove a president from office.

Pelosi did not provide an exact timeline on when she expects a response from Pence. When a reporter asked Pelosi if she hoped to hear back from the vice president later on Thursday, she said: “We would hope.”

It’s unclear if Trump’s Cabinet will support removing him. Elaine Chao, the transportation secretary, resigned following the riot.

Pelosi said Trump had committed “an unspeakable assault on our nation and our people” by urging his supporters to stop Congress from certifying the election of President-elect Joe Biden and Vice President-elect Kamala Harris.

Hours before the mob breached the Capitol, Trump spoke to crowds who had gathered in D.C. The mob later stormed into the building, stopping congressional proceedings for several hours. More than a dozen people were later arrested, and authorities reported four deaths.

Lawmakers returned Thursday night to finish their work. A group of Republicans — eight senators and 139 representatives — still voted in support of overturning the election results. Pelosi criticized them.

“Accountability is also needed for Republicans in Congress who promoted the extreme conspiracy theories that provoked the violence, encouraged the mob, and who, after desecration of the Capitol, went back to the House floor and continued to push the falsehoods and underpinned this assault … on our democracy,” she said.

Pelosi said it was “the overwhelming sentiment” of her caucus to remove the president if Pence and the Cabinet do not act. Many women lawmakers condemned the president in the hours after the attack, with several calling for action to see him removed.

“While it’s only 13 days left, any day can be a horror show for America,” she said.

Pelosi also warned that people who broke into the Capitol carried out “acts of sedition and acts of cowardice.” She said they would face prosecution.

“To those whose purpose was to deter our responsibility, you have failed,” she said.

Pelosi, whose office was broken into during the insurrection, said she was particularly angry about how the rioters had traumatized lawmakers and Capitol staff.

“To meet with them and to see how frightened they were, how traumatized they were because these thugs, these Trump thugs, decided that they would desecrate the Capitol, with no thought of what harm they might do physically, psychologically or in any other way,” she said.

She also told reporters that she had called for the resignation of the Capitol police chief amid questions about security on the complex.

There have been increasing calls to remove Trump from office following Wednesday’s attack, just two weeks before he was set to leave office. The president has spent months questioning the validity of the 2020 election. He lost to Biden, a fact he has refused to acknowledge by claiming widespread voter fraud that courts and election officials have confirmed did not happen.