Attorney General Eric H. Holder Jr. plans to resign, a White House official said Thursday. 

Holder has served in President Barack Obama’s Cabinet since the start of his presidency.

Holder had been rumored to be mulling an exit for months and many expected him to have already departed. But Obama, a longtime friend, made a personal appeal for him to stay on.

Holder revealed in a recent interview that he wrote Obama a lengthy memo outlining “a second-term agenda for the Justice Department.” But many predicted Holder would leave by the end of the year, while Democrats remain in control of the Senate, to make it easier for Obama to replace him.

Democrats are at risk of losing control of the Senate in the upcoming midterm election. Holder has had a rocky tenure as the nation’s first African-American attorney general. 

He has faced near-constant calls for his resignation from conservative lawmakers, who most recently accused him of dragging his feet in investigating allegations that the Internal Revenue Service targeted tea party groups. But some progressives also feel let down by what they see as his failure to more actively pursue civil rights policies.