Former U.S. Rep. Brandon Williams will serve as the next under secretary for nuclear security and also the administrator of the National Nuclear Security Administration at the federal Department of Energy, President-elect Donald Trump wrote on Truth Social Thursday morning.

“Brandon is a successful businessman and Veteran of the U.S. Navy, where he served as a Nuclear Submarine Officer, and Strategic Missile Officer,” Trump wrote. “He is a graduate of Pepperdine University, and the Wharton School of the University of Pennsylvania. Congratulations Brandon!”

Williams, a Republican, most recently served a single term representing New York’s 22nd Congressional District in Central New York. He lost his bid for a second term in November to Democrat John Mannion.

"Mr. President, thank you for the opportunity to continue serving our great nation, especially in a sector that is vital for our national security during such a pivotal time in our history. If and when confirmed by the Senate, I will be honored to lead the tremendous scientific and engineering talent at NNSA. Under the leadership of @ChrisAWright as the Energy Secretary, our critical work at the Dept of Energy will ensure the security of our nation," Williams wrote in a post on X.