Sen. Dick Durbin, a Democrat from Illinois, called on Senate Majority Leader Mitch McConnell tonight to allow lawmakers to pass bipartisan legislation that protects special counsel Robert Mueller's investigation.

"It's time for Mitch McConnell to let us pass the bipartisan legislation once and for all (that) protects the special counsel and lets him finish his business," Durbin told CNN.

Durbin's remarks come hours after President Trump took to Twitter to call on his attorney general, Jeff Sessions, to end Mueller's investigation into Russian election interference.

Some background: Last year, there were two bipartisan bills introduced in the Senate that would protect the special counsel from being fired. The Senate Judiciary Committee held a hearing on the measures in the fall, but there's been little action on the legislation since.

McConnell has told CNN that he thinks Mueller should "be allowed to finish his job."

In an interview with Fox News in April, McConnell said he doesn't believe Trump will fire Mueller, adding he doesn't want legislation on the issue.

"I don't think he should fire Mueller and I don't think he's going to," he said in the interview. "So this is a piece of legislation that isn't necessary in my judgment."