The United States Justice Department is closing its investigation into Federal Reserve Chair Jerome Powell, removing an obstacle to the confirmation of Kevin Warsh, President Donald Trump 's preferred choice to head up the US central bank.

The move by US Attorney Jeanine Pirro, the top federal prosecutor in Washington DC and a Trump ally, for now ends an inquiry which had prompted a key Republican senator to block Trump's bank nominees.

The inquiry had been investigating cost overruns in renovations of the Fed's Washington headquarters but Pirro said she ⁠had ⁠instead asked the Fed's internal watchdog, the Office of Inspector General (IG), to take over.

"The IG has the authority to hold the Federal Reserve accountable to American taxpayers," Pirro said in a social media post.

"I expect a comprehensive report in short order ​and am confident the outcome will assist in resolving, once and for all, the questions that led this office to issue subpoenas ."

What do we know about Powell probe

The Powell probe…