The U.S. Department of Defense has broken its silence on President Donald Trump’s announcement that transgender people will no longer be allowed to serve in the military.

The department said Thursday that it is “awaiting formal guidance from the White House” on the hotly contested policy change, which Trump announced Wednesday morning in a tweet. The president did not provide any details about how the change would be implemented.

Finally, an official, on record statement from DoD about #transgender policy, from spokeswoman Dana White: pic.twitter.com/EWlAw3pIx8 — Aaron Mehta (@AaronMehta) July 27, 2017

Trump claimed he changed the policy after consulting with military experts, although the Pentagon lifted the ban on transgender service members last year after completing an exhaustive review of its military readiness policies.

And both military leaders at the Pentagon and White House officials were caught off guard by the announcement, The New York Times reported. Earlier on Thursday, the United States’ top general echoed the Pentagon’s statement and said he had not received any direction on the matter.

“There will be no modifications to the current policy until the President’s direction has been received by the Secretary of Defense and the Secretary has issued implementation guidance,” Marine General Joseph Dunford, chairman of the military’s Joint Chiefs of Staff, told service chiefs, commanders and senior enlisted leaders.

Kevin Lamarque/Reuters Secretary of Defense James Mattis, right, escorts President Donald Trump as he greets military personnel after attending a meeting at the Pentagon in Arlington, Virginia, on July 20.

During a Wednesday press briefing, White House spokeswoman Sarah Huckabee Sanders could not answer questions about how the ban would affect transgender troops currently serving, and repeatedly said the White House and the Defense Department would address those details.

Sanders provided no additional details on the implementation of the ban on Thursday, saying only that the White House would work with the Pentagon.

“I don’t have a specific timeline,” she said, after repeated questions.