Donald Trump is banning transgender people from the military because they are "expensive and disruptive" - but it has been a "very difficult decision", the White House has said.

The President revealed the move on Twitter, saying he would not allow them to serve "in any capacity".

He said he had made the decision after consultation with armed forces chiefs and that the military "cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail".

Campaigners have called it a "shocking and ignorant attack".

Speaking on Wednesday afternoon, the new White House press secretary said the President had "expressed concerns since this Obama policy came into effect".


Sarah Huckabee Sanders told reporters: "He has also voiced this is a very expensive and disruptive policy... and came to the conclusion that it erodes military readiness and unit cohesion and made the decision based on that."

She added: "The decision is based on a military decision, it's not meant to be anything more than that, obviously it's a very difficult decision it's not a simple one, but the President feels this is the best one for the military."

Reaction to Trump's transgender tweets

:: Analysis: Trump transgender ban is 'policy-making in reverse'

The controversial move reverses plans put in place by Barack Obama to begin accepting transgender recruits, with the first expected to start enlisting this year.

Mr Obama's defence secretary, Ash Carter, ended a ban on transgender people being able to serve openly in the military in June 2016.

An estimated 2,500 to 7,000 transgender people are already on active duty, with another 1,500 to 4,000 in America's military reserves.

Patricia King was the first openly transgender person to serve as an infantry soldier in the US Army.

She told Sky News: "I'm hopeful that, with time and understanding, that we can continue to serve and do so as proudly as we always have.

"The truth of the matter is that transgender people have been serving in the military for quite some time - we simply weren't allowed to do so openly.

"When the decision was made to open transgender service, what it did was allow us to be our whole selves and bring all of that to bear when we come to work to do our job."

After consultation with my Generals and military experts, please be advised that the United States Government will not accept or allow...... — Donald J. Trump (@realDonaldTrump) July 26, 2017 ....Transgender individuals to serve in any capacity in the U.S. Military. Our military must be focused on decisive and overwhelming..... — Donald J. Trump (@realDonaldTrump) July 26, 2017 ....victory and cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail. Thank you — Donald J. Trump (@realDonaldTrump) July 26, 2017

Since October, transgender troops have been able to receive medical care and begin formally changing their gender.

Up to 250 service members are believed to be in the process of transitioning to their preferred genders or been approved to formally change gender.

Mr Trump has not yet explained what would happen to existing transgender people in the military, with those affected urged to contact lawyers by LGBT groups.

The Pentagon said it would provide revised guidance to the US military "in the near future".

Trump ban on trans soldiers 'a military decision'

"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," said Pentagon spokesman Navy Captain Jeff Davis.

Activist and retired US Navy Seal, Kristin Beck, told Sky News: "We've had thousands of people working for a couple of years on this policy, and this policy is totally uplifted and thrown away with a tweet? That's amazingly poor leadership.

"What happens to all these people who currently serve, who were told it is okay to come out, it is okay to serve openly as transgender. Now they're told 'no'? They were given that safe landing zone, now the whole landing zone is on fire and being bombed."

Image: Mr Trump said he consulted with military chiefs

Announcing his decision on Twitter, Mr Trump posted: "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 U.S. Military.

"Our military must be focused on decisive and overwhelming victory and cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail."

Last month, US defence secretary James Mattis put a six-month delay on the acceptance of transgender recruits.

Under Mr Obama's plan, transgender recruits would have to have been "stable" in their preferred gender for 18 months.

House Minority Leader Nancy Pelosi said Mr Trump had unleashed "a vile, hateful agenda, that would blindside thousands of patriotic Americans already serving with honour and bravery."

She said: "On this very day in 1948, president Truman signed the executive order desegregating the US military.

"Here we are, 69 years later, President Trump has chosen this day to commit an act of cowardice... a cowardly act."

UK armed forces allow transgender people to apply and serve openly.