Federal prosecutors have opened a criminal investigation into Federal Reserve Chairman Jerome Powell, he said on Sunday.

In a video announcing the probe, Powell said the US Justice Department served the agency with subpoenas and threatened a criminal indictment over testimony he gave to a Senate committee about renovations to Federal Reserve buildings.

He called the probe "unprecedented" and said he believed it was opened because he drew Donald Trump's ire for refusing to lower interest rates despite repeated public pressure from the president.

The Fed chair is the latest to come into conflict with Trump and then face a criminal investigation by the US Justice Department.

The Justice Department and White House have not yet commented on the apparent investigation.

"This is about whether the Fed will be able to continue to set interest rates based on evidence and economic conditions, or whether instead monetary policy will be directed by political pressure or intimidation," Powell said.

"I have deep respect for the rule of law and for accountability in our democracy. No one, certainly not the chair of the Federal Reserve, is above the law, but this unprecedented action should be seen in the broader context of the administration's threats and ongoing pressure," he went on to say.

The probe, which prosecutors have not confirmed, would signal a fresh escalation in Trump's ongoing dispute with Powell, who the president nominated for the role as Fed chair in 2017.

Trump has repeatedly threatened to remove Powell, whom he has criticised for not cutting interest rates as quickly as the president would have liked. In the second half of 2025, the Fed cut interest rates three times.

The president has consistently blamed his predecessor, Joe Biden, and the central bank's interest rates for the US's economic struggles.

Critics have raised concerns that Trump's pressure to oust the Fed chair would muddy the institution's authority to set interest rates independently from presidents.

North Carolina Senator Thom Tillis, a Republican who is a member of the Senate Banking Committee, said he would oppose the nomination of Powell's replacement by Trump, and any other Fed Board nominee, "until this legal matter is fully resolved".

"If there were any remaining doubt whether advisers within the Trump Administration are actively pushing to end the independence of the Federal Reserve, there should now be none," Tillis said in a statement.

"It is now the independence and credibility of the Department of Justice that are in question," the senator said.

Senator Elizabeth Warren, a Democrat, said she believed Trump's plan was to push Powell off the Fed board for good and "install another sock puppet to complete his corrupt takeover of America's central bank".

"This committee and the Senate should not move forward with any Trump nominee for the Fed, including Fed Chair," she said.

Powell's investigation will be overseen by the US Attorney's Office for the District of Columbia, according to the New York Times, which first reported the probe.

Trump previously took aim at Lisa Cook, a governor at the US central bank, whom he tried to fire over alleged mortgage fraud.

The case was blocked by a US federal court and will be heard by the Supreme Court later this month.