Three Republican House chairman have asked the Department of Justice (DOJ) to provide copies of former FBI Director James Comey's memos, which are said to detail the conversations he had with President Trump before he was fired.

In a letter to Deputy Attorney General Rod Rosenstein on Friday, the lawmakers requested that they receive the memos in unredacted form, arguing that they have a legal basis to review them.

"The Committees request the Department of Justice make copies of the Comey memos available immediately. Copies of any unclassified memos should be produced to all three Committees in unredacted form," they wrote.

"There is no legal basis for withholding these materials from Congress."

House Judiciary Committee Chairman Bob Goodlatte (R-Va.), House Oversight and Government Reform Committee Chairman Trey Gowdy (R-S.C.) and House Permanent Select Committee on Intelligence Chairman Devin Nunes (R-Calif.) all signed the letter.

The request of Rosenstein comes at a time when President Trump is reportedly trying to lay the groundwork for his dismissal.

Rosenstein serves as the gatekeeper to special counsel Robert Mueller, who was appointed - as a result of Comey's firing - to carry out the federal investigation into Russian interference.

Lawmakers have increasingly raised concerns that Rosenstein will soon be out of a job after he ignited the fury of the president by signing off on the FBI raid against Trump's personal lawyer, Michael Cohen.

The raid came about as a result of a tip from the special counsel, The New York Times first reported on Monday.

News of the raid sent the president into a rage. He called it a "witch hunt" and an "attack on our country."

The dispute over the Comey memos, meanwhile, centers on the circumstances of his firing last year.

Comey was spearheading the FBI's investigation into Russian interference before Trump fired him in May, a move his aides first claimed was based off a recommendation by Rosenstein. The president later indicated that he ousted the FBI chief in part because of "this Russia thing."

During an appearance before the Senate Intelligence Committee last year, Comey revealed that he had memorialized these meetings with the president by keeping a set of memos about the interactions.

He said he did so because he felt the president inappropriately asked him to pledge of loyalty to him while he was leading the Russia probe. Trump also asked Comey to drop his investigation into former White House national security adviser Michael Flynn, who was fired after reports revealed that he had lied to investigators about his contacts with a Russian diplomat.

Comey shared one of the memos with a friend who then leaked its contents to the press, but the FBI chief has maintained that it did not contain classified material.

The lawmakers' letter comes as Comey is increasingly stepping back into the spotlight ahead of the release of his new book on Tuesday. In the book, he takes personal shots at the president, commenting on his physical appearance and his moral character.

With the release slated for April 17, an onslaught of media coverage is expected to be met with criticism by those who say he is politicizing the FBI and unfairly attacking the president, among them being Trump allies.

As excerpts of the book have leaked out, Comey has described Trump as a mob boss, a man who is "ego driven" and "untethered to truth."

In response, Trump on Friday took to Twitter to blast Comey as an "untruthful slimeball" and "leaker."

"It was my great honor to fire James Comey!" he tweeted.

Earlier this week, Nunes separately threatened to pursue contempt or impeachment proceedings with FBI Director Christopher Wray and Rosenstein if they did not cooperate with his subpoena related to surveillance abuse during the 2016 presidential campaign.

Rosenstein allowed Nunes and other House Intelligence Committee members to view a two-page document in unredacted form, which detailed what information launched the counterintelligence Russia investigation. The move appeared to dispel the situation for now.

Frustrated Republicans are stepping up their pressure on the DOJ and FBI to provide documents related to a range of investigations they are pursuing, including the FBI's decisionmaking during the 2016 campaign.

- Updated at 7:23 p.m.