If confirmed by the Senate, Barr will replace Sessions, who was pushed out of the post in November after serving for 21 months as attorney general. Trump had criticized Sessions several times during his tenure, frustrated over his decision to recuse himself from special counsel Robert Mueller’s investigation into Russian election meddling.
His chief of staff, Matthew Whitaker, was named acting attorney general in his wake.
Barr served as Bush's attorney general from 1991 to 1993, during the same time Mueller was head of the department's criminal division, The Associated Press reported.
As attorney general, Barr would oversee Mueller's investigation into Russian meddling in the 2016 presidential election, a probe the president has frequently railed against as little more than a politically motivated witch hunt. Democrats are expected to ask for reassurances during confirmation proceedings that Barr won't interfere with the investigation, according to the AP.
Before becoming attorney general in 1991, Barr served as deputy attorney general and as assistant attorney general in charge of the Office of Legal Counsel.
After leaving politics, he spent almost 15 years working for large corporations, according to his biography. He served as general counsel and executive president of Verizon Communications from 2000 until he retired in 2008.
On Friday, the president also announced he plans to nominate current State Department spokeswoman and former Fox News host Heather Nauert to serve as the next ambassador to the United Nations.
Trump added that he plans to announce another big staff change Saturday afternoon, during the Army-Navy football game.