U.S. House Speaker Nancy Pelosi said Friday she intends to transmit articles of impeachment against Donald Trump to the Senate next week, moving to end a taut standoff with Republicans over terms of the president’s trial.

The top Democrat’s announcement virtually assures that a historic trial of Trump on charges of abuse of power and obstruction of Congress begins this month, as anticipated.

But she declined to provide a specific time line for the next steps and did not announce which House Democrats she will ask to spearhead the case in the Senate, saying lawmakers should be ready to vote to appoint the managers some time next week.

“I have asked Judiciary Committee Chairman Jerry Nadler to be prepared to bring to the floor next week a resolution to appoint managers and transmit articles of impeachment to the Senate,” Pelosi said in a letter to her Democratic caucus.

“I will be consulting with you at our Tuesday House Democratic Caucus meeting on how we proceed further.”

Pelosi has withheld the articles since Trump was impeached by the House of Representatives on December 18 over allegations that he improperly pressured Ukraine to investigate his potential 2020 election rival Joe Biden, and that he obstructed the subsequent congressional probe.

The top Democrat in Congress had hoped Senate Leader Mitch McConnell, of Trump’s Republican Party, would provide assurances of what she described as a “fair” trial in which Democrats can subpoena witnesses and documents.

But McConnell — who, like Pelosi, is seen as a wily political strategist — refused to budge, announcing this week he had sufficient Republican votes to conduct a trial without acceding to Democratic demands.

“There will be no haggling with the House over Senate procedure,” he said on Wednesday.

For weeks Pelosi had worn a poker face, leaving Democrats and Republicans alike guessing what and when her next move would be.

On Thursday she revealed only a sliver, saying she could “soon” send the articles to McConnell.

Democrats argue that her delay allowed dramatic new information to emerge before the trial, including Trump’s former national security advisor John Bolton announcing on Monday that he was prepared to testify before the Senate if subpoenaed.

But as Democrats mulled what benefits, if any, there were to further postponing the trial, Pelosi came under increasing pressure to act.

McConnell has said he wants to set initial trial parameters first, then address possible witnesses once the procedure has begun. Pelosi wanted such assurances up front.

“Clearly, Leader McConnell does not want to present witnesses and documents to senators and the American people so they can make an independent judgment about the president’s actions,” Pelosi said in her letter.

Democrats want to hear from four current or former administration officials, including Bolton, Secretary of State Mike Pompeo and White House chief of staff Mick Mulvaney, who have direct knowledge of Trump’s Ukraine dealings.

Getting McConnell to allow witnesses later in the trial would require support from at least four Republicans.

“In an impeachment trial, every senator takes an oath to ‘do impartial justice according to the Constitution and laws,’ ” Pelosi said. “Every Senator now faces a choice: to be loyal to the president or the Constitution.”

Some Republicans saw Pelosi’s announcement as a sign she had backed down in the staring contest with McConnell.

“There is no way to spin it,” added conservative congressman Mark Meadows. “Speaker Pelosi and her Democrat Caucus spent weeks playing games with what is effectively their attempt at overturning an American election.”

The Senate is expected to start its trial this month before the political temperature quickly rises as the nation turns to the 2020 presidential race.

The first vote of the Democratic nomination process, in Iowa, is just weeks away, on Feb. 3.

Five of the candidates — Bernie Sanders, Elizabeth Warren, Amy Klobuchar, Cory Booker and Michael Bennet — are U.S. senators, and their constitutional duty requires them to be seated in the chamber serving as jurors during the impeachment trial.

That will curtail their campaigning in the run-up to Iowa, handing an advantage to former vice president Joe Biden, who is the Democratic frontrunner, and others in the race.