Three weeks after President Donald Trump said that transgender people would not be allowed to serve in the military "in any capacity," Defense Secretary Jim Mattis has left the door open for some to continue being part of the Armed Forces, The Washington Post reports.

Mattis told reporters at the Pentagon that he and his staff are still studying the issue and that we still "have received no direction [from the president] that would indicate any harm to anybody right now," which seemed to raise the prospect that transgender people may be allowed to continue to serve.

Trump sent a tweet last month banning transgender service members, but the announcement was made without coordinating with the military, and the Pentagon has said it is awaiting an official order from Trump before making a policy change.

The defense secretary said this week, according to CNN, that "The policy is going to address whether or not transgenders can serve, under what conditions, what medical support they require, how much time would they be perhaps non-deployable leaving others to pick up their share of everything. There's a host of issues and I'm learning more about this than I ever thought I would."

However, Trump appeared to complicate matters further and doubled down on his tweet that he was banning transgender service by saying that he did the military a "great favor" by doing so.

When Mattis was asked why Trump chose to disclose the decision on Twitter and without a specific policy in place, the defense secretary answered that "the American people elected the commander in chief. They didn't elect me. So the commander in chief in our country, in our system of government, is elected by the people, and he has that authority and responsibility."