U.S. President Donald Trump on Friday faced growing pressure from the fallout of the Capitol riot which many believe he instigated, with Democrats planning a possible second impeachment and Twitter Inc. shutting down his heavily used account.

"If the president does not leave office imminently and willingly, the Congress will proceed with our action," House of Representatives Speaker Nancy Pelosi said in a statement, apparently referring to the impeachment of the Republican president, who has less than two weeks remaining in his term.

Trump was first impeached in late 2019 by the Democrat-controlled House when it brought accusations that he abused the power of his office to boost his chances of re-election. He was acquitted in a subsequent trial in the Republican-controlled Senate.

U.S. President Donald Trump speaks at "Save America March" rally in Washington, United States on Jan. 6, 2021. (Anadolu Agency/Getty/Kyodo)

It is not clear whether lawmakers will be able to oust Trump from office, given that any impeachment requires a two-thirds majority in the 100-member Senate for his conviction and removal.

Nonetheless, some House Democrats have reportedly been preparing to introduce articles charging Trump with "inciting violence against the government" in a bid to overturn his loss to Democrat Joe Biden in the November presidential election.

In another blow to Trump, Twitter shut down his personal account, which has been his preferred means of communicating with his supporters, citing the risk of "further incitement of violence."

He fought back by releasing a series of tweets from his official government account, saying that he will "not be SILENCED." But they were swiftly deleted by Twitter. His election campaign account was also suspended.

In his home state of Delaware, Biden took a cautious stance about backing the Democratic Party's desire to impeach the incumbent.

U.S. President-elect Joe Biden (L) announces retired Army Gen. Lloyd Austin as his choice to be secretary of defense at the Queen Theater Dec. 9, 2020 in Wilmington, Delaware. (Getty/Kyodo)

"What the Congress decides to do is for them to decide," he told a press conference.

He also said it has been his long-held view that Trump, often criticized for his divisive rhetoric and erratic behavior, was "not fit to serve" and that the incumbent "embarrassed us around the world" through Wednesday's deadly riot.

But the president-elect emphasized that his most important job is to address the concerns over the coronavirus pandemic and economic growth immediately after he is sworn in on Jan. 20.

"If we were six months out, we should be doing everything to get him out of office, impeaching him again and trying to invoke the 25th Amendment...But I am focused now on us taking control as president and vice president on the 20th and to get our agenda moving as quickly as you can," he said.

The 25th Amendment allows for the vice president and a majority of the Cabinet to declare the president unfit for office, enabling the vice president to become acting president. Calls have grown for Vice President Mike Pence to invoke the measure, but so far the Trump loyalist does not seem inclined to do so.

Deeply disturbed by Trump's behavior in the final days of his term, Pelosi said Friday that she asked the country's top military general about "available precautions" to stop Trump from ordering a nuclear strike or other military attacks before Jan. 20.

U.S. House of Representatives Speaker Nancy Pelosi speaks at a press conference in Washington on May 23, 2019. (Kyodo) ==Kyodo

"The situation of this unhinged president could not be more dangerous," Pelosi said. "We must do everything that we can to protect the American people from his unbalanced assault on our country and our democracy."

Trump posted a video message on Twitter on Thursday conceding that he will not serve a second term as Congress certified Biden's win in the election. He also said he will shift his focus to "ensuring a smooth, orderly and seamless transition of power."

But he tweeted Friday that he will not attend Biden's inauguration, which is usually attended by the incoming and outgoing presidents to demonstrate unity.

It will be the first time in about 150 years that a sitting president will not take part in the ceremony.

Biden had earlier hoped for Trump's attendance, but he said sarcastically on Friday that the incumbent's plan to be absent is "one of the few things he and I have ever agreed on."

"It's a good thing him not showing up...because he has clearly demonstrated -- he exceeded even my worst notions about him," he added.

On Wednesday, a pro-Trump mob stormed the Capitol as Congress was engaged in the process of certifying the results of the election. Earlier in the day, Trump had called his supporters at a massive rally in Washington to march to the building to demand lawmakers reject the outcome.

Lawmakers were forced to evacuate, while intruders were seen smashing windows and vandalizing offices in the Capitol. Five people died as a result of the chaos, including a police officer and a woman who was fatally shot by police inside the building, according to U.S. media.

Pro-Trump supporters storm the U.S. Capitol following a rally with President Donald Trump on Jan. 6, 2021 in Washington, D.C. Trump supporters gather in the nation's capital to protest the ratification of President-elect Joe Biden's Electoral College victory over President Trump in the 2020 election. (Getty/Kyodo)

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