The rapid transmission of the article against Mr Trump for "incitement to insurrection" will trigger an impeachment trial in the Senate that promises to be one of the most dramatic legislative proceedings in American history.
Senate Majority Leader Mitch McConnell, who will be relegated to minority leader later this month, has not publicly said whether he will convict Mr Trump, although he has privately told confidants he supports the House’s impeachment, The New York Times has reported.
Mr McConnell is reportedly leaving it to individual members of the Senate GOP to vote their consciences on whether to vote to convict – and thereby remove – the president.
At least 17 Republican senators must join with the incoming Democratic majority to convict Mr Trump.
Impeachment proceedings began in the House at 9am on Wednesday, with a vote expected this afternoon.
When passed, Mr Trump will become the first president ever to be impeached twice.
Five Republican lawmakers in the House have said that they believe the president committed an impeachable offence and will vote with Democrats.
The White House is bracing for others to join them.
Mr Trump has just seven days remaining in the Oval Office before President-elect Joe Biden is inaugurated.
There is heavy security around the Capitol building following the assault on the building last week.
A 10-foot-high fence has been erected around the complex, and hundreds of National Guard members are garrisoned in the building with rifles and riot shields stacked up outside.
Many of the troops slept in the visitors’ centre and in the hallways of the Capitol ahead of today’s legislative session.