The US justice department is dropping its investigation into Federal Reserve chairman Jerome Powell over alleged building cost overruns. US Attorney Jeanine Pirro announced that instead, an internal investigation will be conducted by the central bank's inspector general.

President Donald Trump has persistently claimed the costs associated with the Fed's renovation efforts were excessive, which contributed to ongoing tensions between him and Powell. As Powell's term approaches its end, the US Senate is currently evaluating Trump's nominee, Kevin Warsh, for the chairman position. Notably, Republican Senator Thom Tillis has withheld support for Warsh unless the Trump administration ends the investigation into Powell.

White House spokesman Kush Desai emphasized that "American taxpayers deserve answers about the Federal Reserve's fiscal mismanagement" and that the inspector general's authority would best facilitate determining the facts.

The investigation's discontinuation comes as Trump has indicated a desire to see Powell replaced if he does not resign by the end of his term next month. Powell has faced pressure from Trump, who has publicly denounced the Fed's stance on interest rates. In January, Powell released a video detailing the department's prior actions against the Fed concerning the renovations, describing the probe as unprecedented and linked to political pressures.

The renovation project includes crucial updates to the Eccles and 1951 Constitution Avenue buildings, aimed at modernizing facilities that have not seen significant upgrades since their construction in the 1930s.