A top member of Donald Trump’s Republican Party says the soon-to-be-former president is to blame for provoking his supporters to storm the US Capitol.

Mitch McConnell used his last speech as Senate majority leader to lambast Mr Trump over the Capitol riot that resulted in five deaths.

“The mob was fed lies,” Mr McConnell said, referring to Mr Trump’s insistence the presidential election was rigged.

He said the giant mob that attacked the Capitol this month was “provoked by the president and other powerful people”.

“And they tried to use fear and violence to stop a specific proceeding of the first branch of the federal government which they did not like,” Mr McConnell said on the floor of the chamber.

The Republican had been referring to Mr Trump’s inflammatory speech at a “Save America” rally near the White House on January 6.

Mr McConnell reassured the Senate that Joe Biden’s inauguration ceremony at the Capitol will be “safe and successful”.

In his 70-minute speech on the morning of the riots, Mr Trump had called on his supporters to march to the Capitol building and had said “if you don’t fight like hell, you’re not going to have a country any more”.

Mr Trump is accused of inciting the insurrection with fiery rhetoric that sought to delegitimise the victory of Mr Biden in the presidential election, including through allegations of voter fraud.

Last week, the outgoing leader became the first US president to be impeached twice, after an historic vote in the House of Representatives.

Senate Majority Leader Mitch McConnell leaves the Senate chamber on January 19. Photo: Getty

Mr McConnell noted the House of Representatives has not yet transmitted the article of impeachment to the Senate.

But it seems likely to soon hold a trial for Mr Trump.

Once the formal article of impeachment is sent over from the House to to the Senate, the trial can begin, with a two-thirds majority needed to convict.

The Senate is set to be split 50-50 as of Wednesday, handing control of the chamber to Democrats.

Vice president-elect Kamala Harris, a Democrat, will be the tie breaking vote in the event of split decisions, giving her party an edge.

It is unclear how many Republicans might join the Democrats for such a vote, which would also bar Mr Trump from holding office again.

Mr Biden will be sworn in as the 46th president on Wednesday at noon local time in Washington DC (4am Thursday, Australian eastern daylight savings time).

-with AAP