Trump: White House counsel Don McGahn will leave after Kavanaugh’s confirmation

White House counsel Don McGahn was rumored to be on his way out for months, but President Donald Trump finally made it official Wednesday on Twitter.

Trump announced that McGahn would be departing the White House this fall, following the confirmation of Supreme Court nominee Judge Brett Kavanaugh.

“I have worked with Don for a long time and truly appreciate his service!” the president wrote.

McGahn had apparently wanted to exit the White House for some time, but Trump’s tweet may have been unexpected. The Washington Post reports that a source close to McGahn said the White House counsel was surprised, and hadn’t discussed his plans with the president yet.

It wouldn’t be the first time Trump has used Twitter for personnel changes, though he did not specify who would replace McGahn.

And Trump may have a tough time filling the position. McGahn’s successor will have to take over in the midst of special counsel Robert Mueller’s ongoing, high-profile investigation into possible collusion between the Trump campaign and Russia during the 2016 presidential election, which seems to be making Trump increasingly agitated.

McGahn had the thankless job of deflecting Trump’s worst impulses, including halfheartedly making the case to Attorney General Jeff Sessions not to recuse himself from the Russia investigation in March 2017 or threatening to resign rather than fire Mueller in June 2017.

Indeed, McGahn is a central witness in Mueller’s investigation into whether Trump committed obstruction of justice by trying to derail the Russia investigation.

As the New York Times reported earlier this month, McGahn has provided three separate interviews, totaling 30 hours’ worth of testimony, to Mueller’s team about topics including Trump’s decision to fire former FBI Director James Comey, his public and private bashing of Sessions, and his attempts to fire Mueller.

McGahn cooperated with the special counsel’s prosecutors willingly, reportedly fearing that Trump was setting him up to take the fall for obstruction of justice, much like John Dean, Richard M. Nixon’s White House counsel, who pleaded guilty to obstruction charges but eventually cooperated in the Watergate investigation. In August, Trump said McGahn is not a “John Dean type ‘RAT,’” and that he allowed him to testify because he has “nothing to hide.”

Beyond his dealings with the Russia probe, McGahn dutifully carried out the GOP’s agenda to get conservative justices confirmed to the bench, and he’ll depart after likely succeeding in getting Trump’s second Supreme Court pick seated. At least some on Capitol Hill seemed upset by the news of McGahn’s departure, including Iowa Sen. Chuck Grassley:

But Grassley shouldn’t be that surprised. McGahn’s relationship with Trump had reportedly grown increasingly tense; the White House counsel’s cooperation with Mueller likely did little to endear him to his boss.

McGahn wants Emmet Flood, the administration’s top lawyer dealing with the Mueller probe, to take over for him, Axios reported Wednesday. Flood is seasoned at dealing with White House investigations — he worked on former President Bill Clinton’s impeachment team and for the George W. Bush administration, dealing with congressional investigations.

Flood undoubtedly has the experience for the White House counsel job and what could be a very busy few months with the Mueller investigation. If the Democrats retake the House of Representatives in the midterm elections, he should also be ready for a likely onslaught of congressional subpoenas.

Updated with reporting from the Washington Post that says McGahn was surprised by Trump’s tweet.