REUTERS/Mike Segar
Although Trump announced he had consulted with his top military personnel - apparently including Secretary of Defense James Mattis - on the decision, other Pentagon officials seemed out of the loop.
"The tweet was the first we heard about it," a defense official told the Wall Street Journal.
CNN Pentagon correspondent Barbara Starr similarly reported that Pentagon officials were initially unaware of the ban.
Asked directly for a statement, a Pentagon spokesperson bounced Business Insider back to the White House on all questions about the ban.
"We refer all questions about the President's statements to the White House. We will continue to work closely with the White House to address the new guidance provided by the Commander-in-Chief on transgender individuals serving the military. We will provide revised guidance to the Department in the near future," the statement read.
The ban has already generated considerable backlash and confusion.