The House speaker, Nancy Pelosi, has announced she will call a vote on Wednesday to refer articles of impeachment approved last month to the Senate.
The Senate majority leader, Mitch McConnell, subsequently announced that the chamber would take up “housekeeping” items relating to impeachment, possibly including the swearing-in of senators for the trial, later this week and would probably hold opening arguments next Tuesday.
A two-thirds majority of senators would be required to remove Trump from office, which is not seen as likely.
“The president and the senators will be held accountable,” Pelosi said in a statement.
The House judiciary committee chair, Jerry Nadler, told reporters after a morning caucus meeting that Republicans in the Senate must now conduct a “fair” trial.
“The question is, do the Republicans all want to vote to insult the American people?” Nadler said, “to insult the intelligence of anybody watching and to say, ‘We’re going to have a cover up and not a fair trial’?”
Pelosi had delayed relaying the articles of impeachment to the Senate, calling on McConnell to clarify the rules of the trial before she designated prosecutors in the case.
In the immediate wake of Trump’s impeachment last month, McConnell argued that the Senate should not spend long on a trial, saying: “Obviously, I think we’ve heard enough.”
Earlier this week, Trump himself called on senators to dismiss the case quickly.
But support among a moderate bloc of senators for witness testimony at the trial has slowed whatever momentum there once was behind a quick dismissal. The second-ranked Republican in the Senate, John Thune of South Dakota, said on Tuesday he would be “surprised” if the body moved abruptly to dismiss the case.
“I would bet against it,” Thune said.
Under Senate rules, articles of impeachment against a president are prosecuted at trial by designees known as House managers. Pelosi stopped short of naming managers on Tuesday morning. They will be named in the resolution to be passed on Wednesday.
The president has the option of appearing in his own defense but was expected to send a legal team headed by the White House counsel, Pat Cipollone.
“We need to see the arena in which we are sending our managers,” Pelosi had said in a news conference last Thursday, explaining the delay. “Is that too much to ask?”
But under growing pressure from fellow Democrats to move the process ahead, Pelosi took the decision to refer the articles without McConnell supplying a substantive description of the rules in question.
Hakeem Jeffries, chairman of the Democratic caucus, said Pelosi’s decision to delay sending the articles of impeachment to the Senate “created space” for moderate Senate Republicans to push McConnell to allow witness testimony during the trial.
“We are three-quarters of the way to seeing a fair and comprehensive trial in the Senate as it relates to Donald Trump’s abuse of power,” Jeffries said. “That alone is a tremendous objective that has been accomplished.”
Trump was impeached on two articles, for abuse of power and obstruction of Congress, on 18 December. He denies any wrongdoing.