U.S. Supreme Court Chief Justice John Roberts is not interested in presiding over another Senate impeachment trial against former President Trump, Senate Majority Leader Chuck Schumer said in an interview Monday night.

There have been rumblings that Roberts would bow out before the Senate trial, which would make way for Sen. Patrick Leahy, D-Vt., to preside. A Senate source told Fox News that the president pro tempore of the body presides in cases when the impeached individual is no longer president of the U.S.

Schumer told MSNBC that the decision was up to Roberts.

"The Constitution says the chief justice presides for a sitting president. So it was up to John Roberts whether he wanted to preside with a president who is no longer sitting, Trump, and he doesn't want to do it," Schumer said.

House Democrats delivered the impeachment case against Trump to the Senate late Monday for the start of his historic trial, but Republican senators were easing off their criticism of the former president and shunning calls to convict him over the deadly siege at the U.S. Capitol.

President Joe Biden dealt Senate Democrats a blow when he said in an interview that it seems they will be unable to convict Trump for allegedly inciting a crowd prior to a riot at the Capitol.

Biden told CNN that he does not believe that Senate Democrats will get 17 Republicans to vote to convict the former president. He said that his opinion might have been different if Trump remained in office for a few more months.

"The Senate has changed since I was there, but it hasn’t changed that much," Biden said. Biden, however, said he agreed with Democrats that the trial "has to happen."

Fox News' Tyler Olson and the Associated Press contributed to this report