The US House of Representatives has passed legislation calling on Vice-President Mike Pence to invoke his constitutional authority to remove President Donald Trump from office in response to the latter’s role in the deadly mob attack on the Capitol last week.

Democrat Representative Jamie Raskin led the resolution, which calls on Mr Pence, joined by other members of the Cabinet, to oust Mr Trump by activating the 25th Amendment, which allows for the President’s removal if he is deemed “unable to discharge the powers and duties of his office”.

Pushing for Mr Trump’s removal, Mr Raskin, a constitutional law scholar, called on Congress to send the message “that what took place is absolutely intolerable and unacceptable”.

However, Mr Pence has already ruled out invoking the 25th Amendment to remove Mr Trump from power.

In a letter late on Tuesday to House Speaker Nancy Pelosi, Mr Pence said the little-used mechanism should not be “a means of punishment or usurpation” and should be reserved for cases of medical or mental incapacitation.

Doing otherwise would set “a terrible precedent”, he said.

“I urge you and every member of Congress to avoid actions that would further divide and inflame the passions of the moment,” he wrote.

Ms Pelosi has called on Mr Pence to secure the majority of the cabinet and vote to declare Mr Trump unfit to serve.

As the House appeared on the cusp of a bipartisan impeachment of Mr Trump late on Tuesday (local time), Mr Pence encouraged Congress to avoid actions to “further divide and inflame the passions of the moment” and to focus on smoothing the transition to President-elect Joe Biden’s administration.

Ms Pelosi has said if Mr Pence rejected use of the 25th Amendment, the House would move to impeach the President.

On Tuesday, at least four Republicans said they would vote for that. Senate Majority Leader Mitch McConnell, a key Trump ally, also apparently supports such a move.

One of those to desert Mr Trump is Liz Cheney. The third-highest ranked Republican, she was among the first to speak out on Tuesday.

“The President of the United States summoned this mob, assembled the mob, and lit the flame of this attack. Everything that followed was his doing,” she wrote in a statement.

“There has never been a greater betrayal by a president of the United States of his office and his oath to the constitution.”

Ms Cheney is the daughter of Dick Cheney, who was vice-president under George W. Bush.

Her statement came as the House of Representatives began to debate the Democrat-led motion to demand Mr Pence use the amendment to remove Mr Trump from office.

She was followed by Illinois Republican Adam Kinzinger, who has previously said the President should resign or be forced out of office, and New York Republican John Katko.

“It cannot be ignored that President Trump encouraged this insurrection – both on social media ahead of January 6th, and in his speech that day,” Mr Katko wrote in a statement.

“To allow the President of the United States to incite this attack without consequence is a direct threat to the future of our democracy. For that reason, I cannot sit by without taking action.”

Michigan senator Fred Upton said he would also vote for an impeachment.

“The Congress must hold President Trump to account and send a clear message that our country cannot and will not tolerate any effort by any President to impede the peaceful transfer of power from one president to the next,” he said.

Tweet from @NBCNews

The announcements came as Republican leaders in the House refrained from urging their members to vote against impeaching Mr Trump, saying it was a matter of individual conscience.

In a further blow, the President has also reportedly lost the support of Mr McConnell. He is yet to speak publicly but has apparently indicated that he believes that impeaching Mr Trump would make it easier to rid the Republican Party of him and his influence.

A source has told CNN that Mr McConnell is furious about the Capitol attack, and even angrier that Mr Trump has shown no contrition.

Tweet from @PMBreakingNews

The President emerged from a week of self-imposed public silence on Wednesday (Australian time) to visit the construction site of his Mexico border wall in Texas.

He defended his remarks to supporters at a rally before they stormed the seat of Congress and also lambasted Democrats for pushing ahead with a drive to impeach him for an unprecedented second time.

“What I said was totally appropriate,” he said as he left for Texas. “I want no violence.”

He did not answer questions about whether he would resign.

With only eight days left in Mr Trump’s term, chances the Democratic push will result in his removal before Mr Biden takes office on January 20 appear remote. But Democrats say Mr Trump’s actions demand a response.

They could also use an impeachment trial to push through a vote blocking Mr Trump from running for office again.

The Democratic-controlled House was voting on Wednesday afternoon (Australian time) on the resolution calling on Mr Pence to use the 25th amendment.

A vote on an article of impeachment charging Mr Trump with inciting insurrection unless he resigns or Mr Pence moves is likely to quickly follow.

At a meeting to set the rules for the impeachment vote, Democratic Representative David Cicilline told the House rules committee the impeachment drive had the support of 217 lawmakers – enough to impeach Mr Trump.

Mr Cicilline, who helped craft the indictment, said Mr Trump “has had almost a week to do the right thing. He has refused to resign, he has failed to take responsibility, he has demonstrated no remorse”.

-with AAP