Secretary of Defense Jim Mattis unveiled his impending resignation Thursday night; announcing his plan to step down at the Pentagon in February.

“I have been privileged to serve as our country’s 26th Secretary of Defense which has allowed me to serve alongside our men and women of the Department in defense of our citizens and our ideals,” Mattis wrote to the president.

“I am proud of the progress that has been made over the past two years on some of the key goals articulated in our National Defense Strategy: putting the Department on a more sound budgetary footing, improving readiness and lethality in our forces, and reforming the Department’s business practices for greater performance. Our troops continue to provide the capabilities needed to prevail in conflict and sustain strong U.S. global influence,” he added.

President Trump said he plans to announce Mattis’ replacement in the coming days.

“The president’s national security team’s job is to give him advice and it’s the president’s job to make a decision,” said press secretary Sarah Sanders.

Read the full report at the Associated Press.