WASHINGTON (REUTERS, BLOOMBERG) - Congressional Democrats were moving closer to a historic step on Friday (Jan 8) as they weighed impeaching President Donald Trump for a second time, two days after his false claims of election fraud helped encourage a mob that breached the US Capitol.

Top Democratic leaders, including House of Representatives Speaker Nancy Pelosi and Senate Minority Leader Chuck Schumer, called for immediate impeachment proceedings if Vice-President Mike Pence and Mr Trump's Cabinet refuse to take steps to remove Mr Trump from power.

"The President's dangerous and seditious acts necessitate his immediate removal from office," they said in a statement on Thursday evening, accusing Trump of inciting an "insurrection."

Ms Pelosi and Mr Schumer are channeling the genuine fear and anger among Democratic lawmakers that spans the party's ideological spectrum from Representatives Alexandria Ocasio-Cortez of New York to Ms Stephanie Murphy of Florida, the co-chair of the moderate Blue Dog Democrats.

Mr Jim Manley, a former top aide to Senate Majority Leader Harry Reid, a Nevada Democrat, said the assault on the Capitol was so unprecedented that it is in the realm of possibility that House Democrats could proceed.

The demands by both Ms Pelosi and Mr Schumer "indicates that for many, doing nothing is not an option," he said, even though he does not expect enough Republican votes to reach the two-thirds required for an impeachment conviction.

On Thursday evening, Ms Pelosi held a conference call with other top House Democratic leaders, and discussed various options tied to the 25th Amendment and impeachment, and she plans a caucus-wide conference call at noon Friday to discuss what to do, officials said.

A number of Democrats are joining the appeal to invoke the 25th Amendment. But that course, too, has legal and procedural hurdles that would make it difficult to carry out by Jan 20.

As calls for his ouster mounted on Thursday, Mr Trump released a video in which he denounced the violence that has left five people dead.

The Republican President came the closest yet to conceding his loss in the Nov 3 presidential election, promising to ensure a smooth transition to a "new administration". President-elect Joe Biden, a Democrat, is set to be sworn in on Jan 20.

Mr Trump's words were in stark contrast to his speech on Wednesday, when he exhorted a crowd of thousands to descend upon the Capitol as Congress met to certify Mr Biden's election victory.

Rioters stormed the building, overwhelming police and forcing the authorities to transport lawmakers to secure locations for their own safety. A Capitol police officer died from injuries suffered in the assault, the force said late on Thursday, bringing to five the number of related deaths.

With less than two weeks left in Mr Trump's term, it was not clear whether enough time remained to complete the impeachment process. Most Republicans haven't expressed an appetite for another drawn out political battle with the combative president who has just 12 days before he leaves office.

Senator Mitt Romney of Utah, the lone Republican who voted to convict Mr Trump in last year's impeachment trial, pointed out that there's little time for either an impeachment or what likely would be a drawn out battle over the Constitution's 25th Amendment, which provides for the removal of a president.

"I think we have to hold our breath," he told reporters.

One person familiar with her thinking said Ms Pelosi, as of Thursday, night, had not determined a course of action in the wake of Wednesday's siege. She and her advisers believe they have multiple options but that the outcome is unpredictable, according to the person, who asked for anonymity to discuss private deliberations.

Senate Majority Leader Mitch McConnell has stayed mum on any next steps regarding Mr Trump after ripping the futile effort by the president's allies to undo the election that was part of the impetus for the mob to invade the Capitol.

Mr McConnell is married to Transportation Secretary Elaine Chao, who on Thursday resigned saying the attack on Congress "deeply troubled me in a way that I simply cannot set aside." Later on Thursday, Education Secretary Betsy DeVos also resigned.

At least two Republicans, Maryland Governor Larry Hogan and US Representative Adam Kinzinger, said Mr Trump must go. The Wall Street Journal editorial page, seen as a leading voice of the Republican establishment, on Thursday evening called on Mr Trump to resign.

A top Trump ally, Senator Lindsey Graham of South Carolina, said at a news conference Thursday that the riots would "tarnish" the President's legacy and, like many lawmakers in both parties, he thought what happened Wednesday could have been much worse. Still, he didn't think action against Mr Trump was warranted.

"I don't support an effort to invoke the 25th Amendment now," Graham said. "If something else happens, then all options would be on the table." Multiple groups of House Democrats, at the same time, were circulating impeachment articles charging Mr Trump with inciting the riot and seeking to bar him from seeking office again.

Representative Jerry Nadler of New York said he supported bringing impeachment articles straight to the House floor for a vote given the limited time.

For Democratic leaders, there's little risk in pressuring Mr Trump's cabinet and Mr Pence, but impeachment would put the spotlight on Mr Trump instead of on preparing for Mr Biden's incoming administration.

Anger and fallout fears

Nevertheless, many Democrats were pushing to do so anyway. A former senior House aide who keeps in close contact with representatives and staff said that resolve to remove Mr Trump grew over the hours lawmakers were kept behind locked doors to protect them from the intruders.

The former aide said impeachment could move forward regardless of whether Senate Republicans were on board. Ms Pelosi and Mr Schumer also may be trying to prod some GOP lawmakers who are sympathetic to the idea of getting Mr Trump's Cabinet to remove him.

While Ms Pelosi could call the House back to impeach Mr Trump with a simple majority vote on the House floor, the Senate would be compelled to hold a trial presided over by Chief Justice John Roberts.

Given that there are still millions of Trump supporters still on his side, the potential for massive political fallout for Republican senators who cross him might limit how quickly the chamber would act or how many of its members would vote to convict.

Representative Susie Lee, a Nevada Democrat, said Trump "deserves to be removed from office, whether by invoking the 25th Amendment, impeachment, or resignation."

But she said in a statement that without broad, bipartisan support, the likelihood of forcing him out of office before Mr Biden's inauguration "is extremely low." "Especially after the political theater that consumed the Electoral College certification process in Congress," Ms Lee said, "we owe it to our constituents to be honest."

If impeached in the House, Mr Trump would theoretically face trial in the Republican-controlled Senate, which is scheduled to be in recess until Jan 19. Aides to Mr McConnell have not said what he would do if the House approves articles of impeachment.

The Democratic-led House impeached Trump in December 2019 for pressuring the President of Ukraine to investigate Mr Biden, but the Republican-held Senate acquitted him in February 2020.

Only two other presidents in history have been impeached, and none has ever been impeached twice.

Democrats will control the Senate after sweeping two run-off elections in Georgia on Tuesday, but the new senators, Mr Jon Ossoff and Mr Raphael Warnock, will not be sworn in until the state certifies the results. The state deadline to do so is Jan 22, though it could come sooner.

In Thursday's video, a flat-toned Mr Trump struck a conciliatory note seldom seen from the mercurial President, calling for "healing". As recently as Thursday morning, however, Mr Trump was still claiming the election had been stolen, and he stopped short of acknowledging his loss.

Since November, Mr Trump has baselessly railed against the election results as "rigged" due to widespread fraud.

The Trump campaign and its allies filed dozens of lawsuits challenging the vote counts but were almost universally rebuffed in state and federal courts. Election officials have said there is no evidence to back his claims.

Ms Pelosi and Mr Schumer called on Mr Pence and Mr Trump's Cabinet to invoke the US Constitution's 25th Amendment, which allows them to strip the President of his powers if he cannot discharge the duties of his office. But Mr Pence opposes the idea, according to an adviser.

At a news conference to introduce his pick for attorney-general, Mr Biden blamed Mr Trump for instigating the attack but did not comment on his possible removal.

Congress certified Mr Biden's election victory early on Thursday, after the authorities cleared the Capitol. More than half of House Republicans and eight Republican senators voted to challenge some states' election results, backing Mr Trump.

The President has isolated himself among a small circle of die-hard advisers and lashed out at those he perceives as disloyal, including Mr Pence - whom Mr Trump wanted to try to block Congress from certifying Mr Biden's win - according to sources.