President Donald Trump's pick to lead the Department of Veterans Affairs has stepped down from his post as acting secretary as he awaits Senate confirmation to officially serve in the post.

Peter O'Rourke is now serving as acting VA secretary, the VA announced Wednesday. O'Rourke, who served as an enlisted sailor and Air Force officer, was the VA chief of staff and executive director of the department's Office of Accountability and Whistleblower Protection. He is a Lean Six Sigma Master Black Belt, according to his official VA biography.

Wilkie, an Air Force Reserve officer, is now back in his position at the Pentagon where he serves as undersecretary of defense for personnel and readiness.

Trump announced on May 18 that Wilkie would be nominated to serve as VA secretary. Some veterans' groups called on him to step down as acting secretary as he goes through the Senate confirmation process. Federal statute dictates a person cannot serve in an acting role for a position that must be confirmed by the Senate, unless the person previously served as assistant to that office for 90 days, Stars and Stripes reported.

Jacquelyn Hayes-Byrd, the VA's deputy chief of staff, will serve as the VA's acting chief of staff, according to the VA.

Thomas Bowman, the VA's deputy secretary, will re-enter retirement as of June 15, but will still serve as a consultant to O'Rourke. His VA experience has spanned more than a decade while he served as chief of staff to two VA secretaries.

Lawmakers plan to schedule Wilkie's confirmation hearing following Congress's weeklong break for Memorial Day, according to Stripes.

Gina Harkins can be reached at ginah@moaa.org. Follow her on Twitter: @ginaaharkins