Trump wants to implement transgender military ban

Announcing the major policy change on Twitter, Trump said the military should be focused on "overwhelming victory," and not burdened with the "tremendous" medical costs and disruptions that transgender personnel would entail.

"After consultation with my generals and military experts, please be advised that the United States Government will not accept or allow transgender individuals to serve in any capacity in the US Military," Trump tweeted.

The announcement served as a stunning reversal for the military, which has been working with military heads to implement an Obama-era plan to start accepting transgender recruits.

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The previous policy also allowed trans troops already serving to do so openly.

Pentagon officials appeared blindsided by Trump's tweets, with spokesman Navy Captain Jeff Davis referring questions to the White House.

The president thought the previous transgender policy was "disruptive," White House spokeswoman Sarah Huckabee Sanders said, and decided it eroded military readiness and the camaraderie among troops.

"The decision is based on a military decision. It's not meant to be anything more than that," Sanders said.

She did not provide additional details to Trump's bare-bones Twitter announcement.

Defense Secretary Jim Mattis, currently on vacation, only learned of Trump's decision Tuesday after he announced it.

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When pressed on the extent to which Trump consulted with him or the Pentagon, Davis said: "This was something that was the product of consultation."

Last month, Mattis said the five armed service branches could delay accepting transgender recruits until January 1 to finalize some details.

Unanswered questions

Trump's announcement left unanswered a slew of questions, including whether transgender personnel currently serving may soon face getting booted from the military.

Sanders said the Pentagon and the White House would work on the matter together and would "lawfully determine" next steps.

Estimates of transgender troop numbers vary widely. A much-cited Rand Corporation study in 2016 found there are between 1,320 and 6,630 among the 1.3 million active duty service members.

But rights groups say there are about 15,000 active transgender troops.