President Donald Trump hinted on Friday that he would make an announcement about the next chairman of the Joint Chiefs of Staff.

The chairman is the president's top military adviser and oversees US military operations.

According to reports on Friday, Army chief of staff Gen. Mark Milley will be picked for the job.

President Donald Trump will tap Army chief of staff Gen. Mark Milley to take over as the chairman of the Joint Chiefs of Staff, people familiar with the decision told The Washington Post.

The New York Times also reported that Milley would be named chairman, citing administration sources.

Milley, a four-star general, was commissioned in 1980 and has led command and staff positions in eight Army divisions and Special Forces. He has also held positions with the 82nd Airborne and 10th Mountain Division and is well known at the Pentagon and throughout the Army.

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He was deployed as part of Operation Iraqi Freedom and served three tours during Operation Enduring Freedom in Afghanistan, where he was the commanding general of International Security Assistance Force joint command and deputy commanding general of US forces.

Milley's experience with counterinsurgency operations informed the creation of the Army's Security Force Assistance Brigades, which are units tasked with training and advising local partner forces. The first brigade was launched earlier this year and deployed to Afghanistan. Several other brigades have been stationed in the US.

US Army Gen. Milley at a Senate Armed Services Committee hearing on his nomination to be Army chief of staff. REUTERS/Jonathan Ernst

The chairman of the Joint Chiefs oversees US military operations around the world and is the top adviser to the president on military affairs. The current chairman, Marine Gen. Joseph Dunford, is set to retire on October 1, 2019.

Milley, along with Navy chief of operations Adm. John Richardson and Marine Corps commandant Gen. Robert Neller, is expected to complete his current position around the middle of 2019.

Trump hinted a looming announcement about the chairmanship on Friday after confirming his picks for the attorney general and the US ambassador to the United Nations.

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"I have another one for tomorrow that I’m going to be announcing at the Army-Navy game," Trump told reporters at the White House. "I can give you a little hint: It will have to do with the Joint Chiefs of Staff and succession."

Two weeks ago, Trump met with Milley and Air Force chief of staff Gen. David Goldfein, an experienced aviator who is also well respected at the Pentagon.

While Defense Secretary Jim Mattis had a good relationship with Milley, he preferred Goldfein, according to The Post. Trump's decision to go with the Army chief of staff was noted by some current and former officials as another sign of Mattis' waning influence.

If chosen, Milley will need to be confirmed by the Senate.