Air Force Secretary Heather Wilson announced her resignation on Friday.
Wilson said will be leaving in May to become president of the University of Texas at El Paso.
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"It has been a privilege to serve alongside our Airmen over the past two years and I am proud of the progress that we have made restoring our nation's defense," she wrote in her resignation letter.
She became President Donald Trump's first service secretary after being confirmed by the Senate in May 2017.
Trump responded to her announcement on Twitter, writing, "Heather has done an absolutely fantastic job as Secretary of the Air Force, and I know she will be equally great in the very important world of higher education."
Wilson, 58, said that during her tenure at the Air Force, they have "improved the readiness of the force" as well as strengthening their ability to "deter and dominate in space."
Before becoming the 24th secretary of the Air Force, Wilson was a member of the U.S. House of Representatives for more than a decade, representing New Mexico as a Republican. She also served on the National Security Council staff as director for defense policy and arms control under President George H.W. Bush.
She graduated from the Air Force Academy in 1982 as a part of the third class to include women.