WASHINGTON (CBS SF) — Pressure was mounting Sunday for President Donald Trump to leave office in the wake of the deadly siege on the Capitol Wednesday, with House Democrats weighing the next steps necessary for a historic second impeachment.

House Speaker Nancy Pelosi said Democrats will push Vice President Mike Pence to invoke the 25th Amendment to force Trump out on Monday.

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If Pence does not respond, Pelosi said the House will proceed with articles of impeachment.

A recent interview Pelosi gave with ’60 Minutes’ ran on CBS Sunday evening.

“He can only pardon himself from federal offenses. He cannot pardon himself from state offenses and that’s where he’s being investigated in the state of New York,” Pelosi said in the interview.

She said Mr. Trump represents “an imminent threat” to democracy and the Constitution. Two Republican senators have said they want Trump to resign immediately.

To be removed from office, he would need to be convicted by two-thirds of the U. S. Senate or 67 senators. Right now, Republicans still hold onto the majority in the Senate.

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House Majority Whip Jim Clyburn says a vote could come by mid-week, but suggested they could impeach him after President-elect Joe Biden’s first 100 days in office.

“Let’s give President-elect Biden the 100 days he needs to get his agenda off and running. And maybe we will send the articles sometime after that,” he told CNN’s Jake Tapper.

“It’s important to say that the 25th Amendment and impeachment are aimed at two different things right? The 25th Amendment is there to help in situations when the president is unable to do their job. Impeachment is there in situations when the president committed crimes,” UC Hastings law Professor Hadar Aviram told KPIX 5.

She said Trump could lose his pension and perks like secret service protection.

“The goal of that impeachment is only to prevent Trump from having all the perks of being a retired president and to remove him from the possibility of holding office ever again,” said Aviram.

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Meanwhile, Mr. Trump is set to travel to the US-Mexico border on Tuesday and will resume official duties amid this firestorm.