WASHINGTON, D.C. — Federal Reserve Chair Jerome Powell said Wednesday he will remain on the Fed Board until a Justice Department investigation into the central bank's headquarters renovation is complete. Powell has not decided whether to serve another term as governor after his chair term ends in May.

"I have no intention of leaving the board until the investigation is well and truly over with transparency and finality," Powell said. "On the question of whether I will then continue to serve as a governor after my term ends and after the investigation is over, I have not made that decision yet."

"I will make that decision based on what I think is best for the institution and for the people we serve," he said. His term as chair ends in May, but his term as a governor on the Federal Reserve Board runs until 2028.

In January, the Department of Justice subpoenaed Powell and the Federal Reserve Board with questions about a renovation project at the Federal Reserve's Washington, D.C., headquarters. The renovation project had cost overruns that President Trump's administration cited as evidence of mismanagement by Powell.

A federal judge blocked the subpoenas, stating they were served with essentially no evidence to back them up. The judge's ruling prompted U.S. Attorney for the District of Columbia Jeanine Pirro to hold a news conference, and her office subsequently appealed the decision.

U.S. Senator Thom Tillis of North Carolina described the Justice Department probe as bogus. "It confirms just how weak and frivolous the criminal investigation of Chairman Powell is and it is nothing more than a failed attack on Fed independence," Tillis said. Tillis urged Pirro not to appeal the judge's ruling and to let the investigation go.

President Trump nominated economist Kevin Warsh to succeed Powell as Fed Chair. As of Wednesday, Warsh's Senate confirmation process had not progressed beyond a meet-and-greet phase. Tillis is using his seat on the Senate Banking Committee to hold up Warsh's confirmation process.

A yearlong campaign led by President Trump and his allies sought to replace Powell with someone more closely allied with the president. For more than a year, President Trump and his top allies have pressured Powell and other Federal Reserve members to cut interest rates more often. They have used social media posts, cable television segments and allegations of wrongdoing to pressure the Federal Reserve to cut interest rates.

Powell said he would remain as chair pro tempore if Warsh was not confirmed before his term ended.