02 Gen Lloyd Austin FILE
CNN  — 

President-elect Joe Biden has named retired Army Gen. Lloyd Austin as his nominee for secretary of defense, the Biden transition team announced Tuesday.

The former commander of the US Central Command would make history as the first Black person to lead the Pentagon if confirmed by the US Senate.

“Today, I ask Lloyd Austin to once more take on a mission for the United States of America–this time as the secretary-designate of the Department of Defense. I know he will do an outstanding job,” Biden wrote in an op-ed published by The Atlantic on Tuesday.

“In his more than 40 years in the United States Army, Austin met every challenge with extraordinary skill and profound personal decency. He is a true and tested soldier and leader. I’ve spent countless hours with him, in the field and in the White House Situation Room. I’ve sought his advice, seen his command, and admired his calm and his character. He is the definition of a patriot.”

Biden will formally introduce Austin as his nominee at a Wednesday event in Wilmington, Delaware.

Austin would assume one of the most prominent roles in Biden’s administration. The secretary of defense controls the nation’s largest government agency and commands troops around the world.

Austin has worked closely with Biden in the past. While Biden was vice president, Austin served as the vice chief of staff of the Army and commanding general of US forces in Iraq, and later the commander of CENTCOM. Biden and Austin had discussions on a range of issues, including those in the Middle East and Central and South Asia.

“Above all, I chose Lloyd Austin as my nominee for secretary of defense because I know how he reacts under pressure, and I know that he will do whatever it takes to defend the American people,” Biden wrote in the op-ed.

The President-elect continued, “When the Islamic State emerged as a terrorist threat in Iraq and Syria, endangering the security of America’s people and allies, President Obama and I turned to Austin, who then led U.S. Central Command. He designed and executed the campaign that ultimately beat back ISIS, helping to build a coalition of partners and allies from more than 70 countries who worked together to overcome a common enemy.”

Austin would need a congressional waiver to be confirmed for the civilian post because federal law requires seven years of retirement from active duty before taking on the role. Austin retired from active-duty service only four years ago.

Though the use of the waiver is rare, retired Marine Gen. James Mattis received a waiver from Congress in 2017 to serve as President Donald Trump’s defense secretary. Some Democrats in Congress at the time expressed concerns about setting aside the precedent of maintaining civilian leadership in the military, but the waiver was ultimately approved by both chambers, allowing Mattis to serve in the position until his departure in December 2018.

Senate Democrats are uneasy about granting the waiver, CNN reported Tuesday. The early resistance was a sign that Biden and his team will need to lobby their party to fall in line behind the historic pick with a narrowly divided Senate and little margin for error next year.

CNN had previously reported that Austin was Biden’s pick for the role. Biden reached out to Austin over the weekend to offer the job, according to a source familiar with the decision. Austin emerged as the leading candidate last week, the source said.

Austin was among three final contenders for the role, CNN had reported. Michèle Flournoy, a veteran Pentagon official who served as under secretary of defense for policy in President Barack Obama’s administration, and Jeh Johnson, a former secretary of homeland security, were also under consideration.

The announcement of Biden’s secretary of defense comes two weeks after the President-elect announced other key members of his national security and foreign policy teams. Those he has named include Avril Haines, a former top CIA official and deputy national security adviser, to lead the US intelligence community; Alejandro Mayorkas, a former deputy secretary at the Department of Homeland Security, as Homeland Security secretary; Antony Blinken, his top foreign policy aide, as secretary of state; and Linda Thomas-Greenfield, a career foreign service official, to be the US ambassador to the United Nations.

This story has been updated with additional information about Austin’s announcement and information about Biden’s previous administration announcements.

CNN’s Manu Raju and Ted Barrett contributed to this report.