President Trump faces a "firestorm of litigation" over his proposed ban on transgender US military personnel, a British transgender officer says.
Abigail Austen told Channel 4 no employment tribunal would support President Trump's proposed ban.
Mr Trump said transgender personnel would burden the US military with "tremendous medical costs and disruption".
Ms Austen is Britain's first transgender Army officer.
She said: "When you're sat there in a foxhole, what you really want to know is if the person next to you has got your back.
"That doesn't matter... whether you're a man, woman or a giraffe - it's whether you have the talent to do the job."
She also said that, according to a report published last year, at least 2,500 transgender individuals in the US military came forward in the past year.
Ms Austen said they "will now be looking for some kind of succour from the Pentagon and from the White House itself as to where their direction and their fate now now lies".
She added: "If President Trump doesn't sort this, he will face a firestorm of litigation.
"I can't think of employment tribunal anywhere in the world that will support what is effectively a dismissal policy conducted over social media."
Ms Austen is about to serve in Afghanistan as part of the Nato mission there.
Mr Trump made his announcement on Wednesday in a series of tweets, in which he said: "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".
Former RAF pilot Ayla Holdom, who began transitioning in 2010, has praised UK defence leaders for publicly supporting their transgender staff.
UK Maritime Forces Rear Admiral Alex Burton said: "I am so glad we are not going this way."
Second Sea Lord Vice Admiral Jonathan Woodcock tweeted that he was "proud" of the Royal Navy's transgender personnel.
Ms Holdom, who piloted a search and rescue helicopter for seven years, said supportive comments matter "hugely".
"These people deserve respect," she added. "We have a better service and a stronger team by being diverse, by not all being the same."
The Obama administration decided last year to allow transgender people to serve openly in the military.
But in June, Defence Secretary James Mattis agreed to a six-month delay in the recruitment of transgender people.