WASHINGTON (AP) — Senate Republican leader Mitch McConnell on Tuesday explicitly blamed President Donald Trump for the deadly riot at the Capitol, saying the mob was “fed lies” and that the president and others “provoked” those intent on overturning Democrat Joe Biden’s election.

Ahead of Trump’s historic second impeachment trial, McConnell’s remarks were his most severe and public rebuke of the outgoing president. The GOP leader is setting a tone as Republicans weigh whether to convict Trump on the impeachment charge that will soon be sent over from the House: “incitement of insurrection”.

“The mob was fed lies,” McConnell said. “They were 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.”

The Republican leader vowed a “safe and successful” inauguration of Biden at the Capitol, where final preparations were underway yesterday amid heavy security.

Trump’s last full day in office Tuesday was also senators’ first day back since the deadly Capitol siege and since the House voted to impeach him for his role in the riots — an unparalleled time of transition as the Senate prepares for the second impeachment trial in two years and presses ahead with the confirmation of Biden’s Cabinet.

Three new Democratic senators-elect are set to be sworn into office Wednesday, shortly after Biden’s inauguration, giving the Democrats the barest majority – a 50-50 Senate chamber. The new vice-president, Kamala Harris, will swear them in and serve as an eventual tiebreaking vote.

The Democrats, led by Senate Democratic leader Chuck Schumer, will take charge of the Senate as they launch a trial to hold the defeated president responsible for the siege while also quickly confirming Biden’s Cabinet and being asked to consider passage of a sweeping new US$1.9-trillion COVID-19 relief Bill.

“The inauguration of a new president and the start of a new Administration always brings a flurry of activity to our nation’s Government,” Schumer said in remarks on the Senate floor Tuesday morning. “But rarely has so much piled up for the Senate as during this particular transition.”

Making the case for Trump’s conviction, Schumer said the Senate needs to set a precedent that the “severest offence ever committed by a president would be met by the severest remedy provided by the Constitution — impeachment,” and disbarment from future office.

McConnell and Schumer conferred later Tuesday about how to organise the evenly divided chamber and how to balance the trial with other business. Leaving a meeting with the Republican leader, Schumer would only say the two had “discussed a whole lot of issues”.

Similarly, McConnell told reporters the two had a “good meeting” but offered no details.

Five of Biden’s nominees had committee hearings Tuesday as the Senate prepared for swift confirmation of some as soon as the president-elect takes office, as is often done particularly for the White House’s national security team. Many noted the harrowing events at the Capitol on January 6.

Biden’s nominee for secretary of the Department of Homeland Security, Alejandro Mayorkas, vowed to get to the bottom of the “horrifying” siege. The nominee for director of national intelligence, Avril Haines, testified of her own “eerie” feeling coming to the Capitol complex after “how truly disturbing it was” to see the attack on the building unfold.

The start of the new session of Congress was also forcing lawmakers to come to terms with the post-Trump era, a transfer of power that Trump’s mob of supporters tried to prevent after he urged them to storm the Capitol as Congress was tallying the electoral college vote confirming Biden’s election.