Five former U.S. attorneys general urged the U.S. Senate this week to quickly confirm Alabama Sen. Jeff Sessions to lead the Justice Department in the coming Trump administration.

The signatories of the letter include former attorneys general Michael Mukasey, Alberto Gonzales, John Ashcroft, William Barr and Ed Meese. The five men served under Republican presidents.

"All of us know [Sessions] as a person of honesty and integrity, who has held himself to the highest ethical standards throughout his career, and is guided always by a deep and abiding sense of duty to this nation and its founding charter," they wrote. "Based on our collective and extensive experience, we also know him to be a person of unwavering dedication to the mission of the department — to assure that our country is governed by the fair and even-handed rule of law."

"Sessions is superbly qualified by temperament, intellect, and experience" to serve as the head of the Justice Department, they added.

Sessions' confirmation proceedings will likely prove contentious, as his nomination has rankled progressive opponents of President-elect Trump because of the senator's populist and nationalist approach to politics. However, Senate Democrats will be unable to scuttle his nomination unless they can find three Republican senators who oppose him.