The administration has also taken aim at the independent Fed by initiating an investigation into Powell over renovation cost overruns and seeking to oust governor Lisa Cook.
Regarding the DOJ probe, Trump said: “I’m not playing. I have to find out.”
Trump named former central banker Kevin Warsh to succeed Powell, but the Senate must confirm him.
Warsh faces a hearing next Tuesday but remains at an impasse with lawmakers like Senator Thom Tillis, who vowed to hold up the nomination until the investigation is resolved.
However, Treasury Secretary Scott Bessent said he is “very optimistic” that Warsh will be chair on time.
David Wessel of the Brookings Institution noted it is “hard to figure out what rational motive” the administration has for prolonging the probe if it delays its own nominee.
Powell first took the helm of the Fed during Trump’s first presidency in 2018 and was reappointed under Joe Biden in 2022.