Senate Republicans and Democrats on Thursday introduced a bill which seeks to prevent President Trump from firing or blocking Special Counsel Robert Mueller from proceeding with the probe of his ties to Moscow. Congress has increasingly asserted its authority over the issue.

Senators from both parties have voiced out the fear that Trump might fire Mueller, who was appointed to investigate and determine if collusion between Russia and the 2016 presidential campaign took place.

Why senators want to protect Mueller

President Trump fired Federal Bureau of Investigations director James Comey in May over his probe on the Russia interference.

Recently, he blasted his own attorney general, Jeff Sessions for distancing himself from the ongoing investigation.

With indications that the investigation by the Mueller panel is progressing, congressional senators sought a law that could protect the special counsel. Mueller was appointed in May to determine whether Russia colluded with the Trump campaign. Sources told reporters that Mueller had hired a grand Jury to probe the allegations of Russian interference.

Mueller convenes grand jury subpoenas

The sources hinted that the grand jury subpoenas were convened following the June 2016 meeting of Trump Jr., the President’s son-in-law Jared Kushner and a Russian lawyer.

Russia has denied influencing the U.S.

presidential election, and Trump has repeatedly disputed the allegations that his campaign and associates colluded with Moscow.

Republican Senator Lindsay Graham stated that the proposed legislation seeks to allow judicial review of any move to dismiss a counsel to ensure that reason for which it was appointed is accomplished.

The bill was co-sponsored by Sen. Cory Booker, a Democrat.

Another measure similar to that sponsored by Senators Graham and Booker was introduced by Sen. Thom Tillis, a Republican and Sen. Chris Coons, a Democrat.

Coons said he hopes that the two groups would work with other senators and seek more sponsors from both the Republicans and Democrats to come up with just one bill that can scale through.

He added that both groups were discussing with the Senate Judiciary Committee hoping that they would work on the bill, leading to a vote on the floor of the Senate.

The bills come at a time when the Senate is preparing to embark on recess in August. The lawmakers will be reconvening in early September.

Lawmakers have recently been pushing for legislations that would increase Congress overwhelming influence on US foreign policy.