University of Iowa graduate Matt Whitaker’s days as temporary head of the Justice Department are dwindling after President Trump announced his pick for a nominee for a new U.S. attorney general Friday.

William Barr, the former attorney general under George H.W. Bush, is the leading candidate for Trump’s nominee to permanently replace ousted Attorney General Jeff Sessions, news outlets reported Trump said. If he’s confirmed by the Senate, Barr will take over the position from Whitaker.

Trump appointed Whitaker to the role of acting attorney general on Nov. 7 after the president asked Sessions to resign. His appointment was unusual, invoking a never-before-used act that grants a president the power to appoint high-ranking officials until a candidate can be vetted by the Senate.

Critics of Whitaker’s appointment called him to recuse himself from overseeing the Russia probe because of critical views Whitaker expressed about the investigation, headed by Special Counsel Robert Mueller.

Whitaker was previously Sessions’ chief of staff. It’s unclear what position he would take if replaced.

Iowa Sen. Chuck Grassley, the outgoing Republican head of the Judiciary Committee, has called for President Trump to hurry his nomination.

“Within a few weeks the president ought to have a nominee up here,” Grassley previously told reporters. “It’s bad for the Justice Department to have 20 acting people, so the shorter we have an acting attorney general, the better.”

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