Senate Majority Leader Mitch McConnell rejected calls by Democrats to summon new witnesses in the upcoming impeachment trial.

Minority Leader Chuck Schumer, a New York Democrat, requested McConnell subpoena top Trump administration officials who had refused to testify before weekslong House impeachment proceedings. The list of requests includes former national security adviser John Bolton and acting White House chief of staff Mick Mulvaney.

But McConnell, a Kentucky Republican, said the Senate trial should weigh the evidence produced by the House and should not summon new witnesses. The witnesses are challenging House subpoenas in federal court, and those cases could take months to resolve. House Democrats decided to move ahead with impeachment rather than wait for the court to decide whether the witnesses should be compelled to testify.

“It is not the Senate’s job to leap into the breach and search desperately for ways to get to guilty,” McConnell said. “That would hardly be impartial justice. The fact that my colleague is already desperate to sign up the Senate for new fact-finding, which House Democrats themselves were too impatient to see through, well, that suggests that even Democrats who do not like this president are beginning to realize how dramatically insufficient the House’s rushed process has been.”

The House is poised to pass articles of impeachment on Wednesday with no Republican votes. The Senate will consider the articles at a trial beginning in January.

Schumer said Monday he believes he can garner the 51 votes needed to force the Senate to subpoena the witnesses and documents Democrats are seeking. But it would require four Republicans to cross party lines and vote with Democrats.

Schumer responded immediately to McConnell's rejection of the witness list, suggesting the GOP is fearful of what the witnesses would say.

"I did not hear a single sentence, a single argument as to why the witnesses I suggested should not be given testimony," Schumer said. "Impeachment trials, like most trials, have witnesses. To have none would be an aberration. Why is the leader, why is the president, so afraid of having these witnesses come testify?"

Schumer, however, is not willing to cut a deal with GOP lawmakers that would include summoning their own witness list. The Republican list includes House Intelligence Committee Chairman Adam Schiff, a California Democrat who the GOP suspects of orchestrating a whistleblower complaint against the president that helped launch the impeachment inquiry. Some Republicans also want to summon the son of former Vice President Joe Biden, Hunter Biden, who held a lucrative Ukrainian gas company job that President Trump hoped government officials would investigate.