Trump and his closest backers in the Republican Party had spent weeks inflaming the president’s supporters with false claims that the election had been “stolen” from them, and in a speech shortly before the attack on the Capitol began, Trump told the crowd: “If you don’t fight like hell you’re not going to have a country any more”.

“President Trump gravely endangered the security of the United States and its institutions of Government,” the article of impeachment says. “He threatened the integrity of the democratic system, interfered with the peaceful transition of power, and imperiled a coequal branch of Government.”

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Trump supporters storm the U.S. Capitol

Trump supporters storm the U.S. Capitol

Trump, it says, “has demonstrated that he will remain a threat to national security, democracy, and the Constitution if allowed to remain in office, and has acted in a manner grossly incompatible with self-governance and the rule of law.”

The impeachment resolution was introduced by Representatives David Cicilline of Rhode Island, Ted Lieu of California, Jamie Raskin of Maryland and House Judiciary Committee chairman Jerrold Nadler of New York.

Timing on a potential Senate trial remains unclear. The Senate is required to move promptly when it receives articles of impeachment from the House, and some Democrats worry that a Senate trial would consume the beginning of the Biden administration, making it harder for the new president to carry out his agenda.

“It just so happens that if it didn’t go over there for 100 days, it could – let’s give President-elect Biden the 100 days he needs to get his agenda off and running, and maybe we’ll send the articles sometime after that,” Representative James Clyburn, the No 3 House Democrat, told CNN on Sunday.

‘A level of madness’: second Republican senator urges Trump to resign

But Representative Steny Hoyer, the No 2 House Democrat, said on Monday that he expected the vote to impeach Trump will be on Wednesday, and after that he wants the resolution sent over to the Senate without delay, according to CNN.

President-elect Joe Biden said on Monday that he has asked lawmakers whether they might be able to take up impeachment and other priorities, including confirming his cabinet nominees, at the same time.

“Can we go half-day on dealing with impeachment, and half-day getting my people nominated and confirmed in the Senate as well as moving on the package?” Biden said. “I haven’t gotten an answer from the parliamentarian yet.”

Later on Monday, The Washington Post reported that Chuck Schumer, the Senate Democratic leader, was considering whether to use a rare authority granted after the September 11, 2001, terrorist attacks to reconvene the Senate during an emergency, according to a congressional aide.

The Senate has been in recess since it finished certifying the Electoral College vote last week. For it to be called back before its scheduled date of January 19, Majority Leader Mitch McConnell would have to agree to the move.

The number of lawmakers from Trump’s party who have called for the president’s resignation or removal from office has grown in recent days.

Two Republican senators, Alaska’s Lisa Murkowski and Pennsylvania’s Pat Toomey, have called on Trump to step down, while a third, Ben Sasse of Nebraska, said he would “definitely consider” any article of impeachment sent from the House.

Lawmakers on Monday also pushed forward with a separate resolution attempting to remove Trump from office.

During a brief session on the House floor, Hoyer tried to bring up a resolution calling on Pence to invoke the 25th Amendment – essentially an emergency procedure written into the Constitution to remove a president when he is no longer capable of carrying out his duties.

The motion was blocked by Alex Mooney, a Republican from West Virginia, but the House is expected to move forward with the resolution on Tuesday. It was also introduced by Representative Raskin of Maryland.

House Speaker Nancy Pelosi said on Monday that Pence would be given 24 hours to respond once the 25th Amendment resolution passes, and she lashed out at Republicans seeking to block it, saying they were “enabling the president’s unhinged, unstable and deranged acts of sedition to continue.”

“The president’s threat to America is urgent, and so too will be our action,” Pelosi said.

Impeachment or 25th Amendment: How could Trump be removed from office?

Some in the Republican Party have argued that impeachment could either further inflame Trump’s supporters or threaten national unity, a position that has found little favour among Democrats.

Biden has said impeachment is a decision for Congress to make. But he emphasised on Monday that perpetrators of last week’s crimes must be held accountable for their actions.

“I think it’s critically important to do a real, serious focus on holding those folks who engaged in sedition, and threatened lives, defaced public property, caused great damage, to be held accountable,” Biden said after receiving his second dose of coronavirus vaccine.

Last Wednesday, Trump supporters stormed the Capitol building as lawmakers were moving to ratify Biden’s victory.

The violent siege, which left five people dead, came soon after Trump had again vowed never to accept the results of the election and called on supporters to “fight like hell”. He also expressed disappointment that Pence had resisted his appeal to unilaterally and unconstitutionally reject the Electoral College count.

According to first-person accounts, some of those who breached the Capitol had called for the execution of Pence. At least one person dressed in paramilitary attire was pictured brandishing zip ties of the sort used as restraints. Another intruder, prosecutors said, was armed with a semi-automatic rifle and 11 Molotov cocktails.

Hours into the violence, Trump appealed to his supporters to “go home,” while also calling them “very special” and telling them he loved them. In a later scripted address, he sought to distance himself from the unrest, saying that those who had committed acts of violence did not “represent our country”.

But the condemnation did little to assuage concerns of lawmakers who accused Trump of inflaming the rage of his supporters with disproved claims of widespread voter fraud and inciting the day’s violence.

Additional reporting by Owen Churchill