WASHINGTON (AP) -- Congress has headed home for the holidays leaving plans and a possible timeline for President Donald Trump's impeachment trial in disarray.

Democratic House Speaker Nancy Pelosi insisted Thursday that Senate Republicans must provide details on witnesses and testimony before she would send over the charges for Trump's trial. No deal, replied Senate Majority Leader Mitch McConnell after meeting with his Senate Democratic counterpart.

"We remain at an impasse," he said.

As darkness fell and lawmakers prepared to depart for the year, McConnell wondered from the Senate floor why in the world the Republicans should give ground to persuade House Democrats "to send us something we do not want."

McConnell and the Democrats' Senate leader, Chuck Schumer of New York, met for about 20 minutes in their first attempt to negotiate the contours of an agreement on running the rare Senate impeachment trial that was expected to start in January.

McConnell favors a swift trial, without the new witnesses Democrats want, and he holds a clear tactical advantage if he can keep his 53-member Senate majority united. Schumer, who also met privately with Pelosi, has to bet that GOP senators won't hold the line and Republicans will peel away as public pressure mounts for a fuller trial.

For the record, Sen. Lindsey Graham of South Carolina said he had met with Trump and "he is demanding his day in court."

McConnell, who has drawn criticism for saying he won't be an impartial juror, said the Democrats were ``too afraid'' to send the charges to the Senate, where Trump would be expected to be acquitted by the Republican majority.

We'll see, he said, "whether the House Democrats ever work up the courage to take their accusations to trial."

Pelosi said that McConnell "says it's OK for the foreman of the jury to be in cahoots with the lawyers of the accused. That doesn't sound right to us."

Dismissing the idea that Democrats would hold off the proceeding indefinitely to prevent Trump from being acquitted, Schumer said there will almost certainly be a trial.

"There's an obligation under the Constitution to have a trial," Schumer told The Associated Press.

He noted that even the Democratic senators campaigning for the party's presidential nomination, with early state voting starting in February, are prepared to return to Washington to sit for the days-long proceedings. "The Constitution requires it," he said.

Wednesday night's House vote, almost entirely along party lines, made the president just the third in US history to be impeached. The House impeached Trump on two charges _ abusing his presidential power and obstructing Congress _ stemming from his pressure on Ukraine to announce investigations of his political rival as Trump withheld US aid.

Pelosi's procedural delay in taking the next step _ apparently in search of leverage with Senate Republicans in locking in trial arrangements _ threw a wrench into the expected timing.

"So far we haven't seen anything that looks fair to us," she had said Wednesday night. On Thursday at the Capitol, she said, "We'd like to see a fair process, but we'll see what they have and will be ready for whatever it is."

Trump mocked on Twitter: "Now the Do Nothing Party want to Do Nothing with the Articles."

Both parties said public opinion was with them after the House impeachment vote.

Trump claimed polling showed him leading all potential Democratic opponents for next fall's election.

Pelosi said, "We've been hearing from people all over the country. Seems like people have a spring in their step because the president was held accountable for his reckless behavior."

With elections in mind, Trump welcomed Democratic Rep. Jeff Van Drew into the GOP after the New Jersey freshman said he would be changing parties because he opposed impeachment.

Pelosi, pressed about next steps for impeachment, wouldn't say. She and her Democrats are insisting on more witnesses, testimony and documents than McConnell appears willing to provide before they name the House "managers" who would prosecute Trump in the Senate.

"The next thing will be when we see the process that is set forth in the Senate," Pelosi said. "Then we'll know the number of managers we may have to go forward and who we would choose."

Not yet.

On the Senate floor, McConnell described the House actions against Trump as "the most rushed, least thorough and most unfair impeachment inquiry in modern history."

Fighting back using McConnell's own words, Schumer said the Republican leader was plotting the "most rushed, least thorough and most unfair" impeachment trial in history by declining to agree to call witnesses, including former Trump national security adviser John Bolton, who declined to testify before the House.

"McConnell claimed the impeachment was motivated by partisan rage,"  said Schumer. "This from the man who said proudly, `I am not impartial.'

"What hypocrisy." (AP)