Not long after, his Democratic counterpart, Senate Minority Leader Chuck Schumer, issued a pointed statement reminding senators must take an oath to be impartial.
"Everything I do during this, I'm coordinating with White House counsel," McConnell said in an interview with Fox News' Sean Hannity Thursday evening. "There'll be no difference between the president's position and our position as to how to handle this."
"Exactly how we go forward, I'm going to coordinate with the president's lawyers," McConnell added. "The case is so darn weak coming over from the House. We all know how it's going to end. There is no chance the president is going to be removed from office. My hope is that there won't be a Republican who votes for either of these articles of impeachment."
Schumer released a statement Friday on the heels of McConnell's comments, reminding his colleagues about the oath they must take before the trial to "render impartial justice."
"If articles of impeachment are sent to the Senate, every single senator will take an oath to render ‘impartial justice.' Making sure the Senate conducts a fair and honest trial that allows all the facts to come out is paramount," Schumer said, citing the Senate rules for impeachment trials.
Former Sen. Tom Daschle of South Dakota, who served as the Senate's Democratic Leader during former President Bill Clinton's impeachment, said on Thursday that he strictly avoided contact with the White House at the time, citing his role as a juror.
"I felt strongly that, as a juror, contact or coordination with the White House was not appropriate," Daschle told Axios Thursday. "I had no conversations with the president or his staff during the entire time of the proceedings ... times have changed."
On Friday, Daschle clarified his remarks, and told Axios that while he didn't have contact with the White House during the Clinton impeachment trial, his staff did.
"There was a need to coordinate on many levels," Daschle said.
In the U.S. Constitution, Article I, section 3, clause 6 specifies that senators, when sitting on a trial of impeachment, "shall be on Oath or Affirmation" meaning they take taking is a "juror’s oath,"in addition to the "legislator’s oath" they already carry.
Further, Senate rules for impeachment trials require senators to "solemnly swear (or affirm) that in all things appertaining to the trial," they "do impartial justice according to the Constitution and laws" -- meaning senators should not make decisions based off party affiliation, according to the Constitution.
Other Democrats jumped on McConnell's comments.
"The Majority Leader proudly announcing he is planning to rig the impeachment trial for Trump," Sen. Chris Murphy, D-Conn., said in a tweet Thursday.
The impeachment articles accuse President Trump of abuse of power and obstruction of Congress. The Constitution mandates a two-thirds majority, or 67 senators, must vote to convict the president.
"There is zero chance the president obviously will be removed from office and I'm hoping we'll have no defections at all," McConnell told Hannity. In fact, McConnell said he envisions one or two Democrats in the Senate may vote with Republicans.
"It wouldn't surprise me if we got one or two Democrats," McConnell said. "It looks to me over in the House, the Republicans seem to be solid and the Democrats seem to be divided."
Earlier on Thursday, White House counsel Pat Cipollone and Legislative Affairs Director Eric Ueland met behind closed doors with McConnell in his Capitol Hill office for more than an hour and a half to discuss, among other things, impeachment.
"We continue to work closely with Senate Republicans, as well as other members of Congress on the questions [surrounding impeachment], and we’ll continue to be very cooperative and very collaborative with our friends up here on the Hill as we work through this process," Ueland said.
Republican senators have hinted that they don't foresee a Senate trial with witnesses, largely because they want a shorter impeachment trial rather than longer one.
"The Senate has two choices," McConnell said Tuesday. "They could go down the path of calling witnesses and basically having another trial or it could decide and again, 51 members to make that decision - that they've heard enough, and believe they know what would happen and it could move the vote on the two articles sent over by the House."
Trump, who has said he wants multiple witnesses at a Senate trial, including Joe and Hunter Biden, claimed at an Oval Office photo op on Friday claimed he has no preference on the length of a trial after talking to McConnell and Senate Judiciary Committee Chairman Lindsey Graham, who prefer, for now, a shorter trial, seeing no need for witnesses at this stage.
"I'll do long or short. I've heard Mitch. I've heard Lindsey. I think they are very much in agreement on some concept. I'll do whatever they want to do. It doesn't matter," he said, before adding: "I wouldn't mind a long process because I'd like to see The Whistleblower."
ABC News' Trish Turner contributed to this report.