Servicewomen in the Royal Air Force (RAF) are no longer allowed to wear skirts when marching on parade.
The restriction was issued in a bid to make the RAF’s uniform more inclusive for transgender personnel.
“We have men who want to live as women, women who want to live as men and personnel who do not identify with any gender,” a source told The Sun.
“The view was we need a uniform policy to cut through all of that and say there is one uniform for everyone and that’s that. It’s about including people and encouraging diversity.”
The change in uniform is also understood to have been introduced after women complained that it was uncomfortable to march while wearing skirts.
Women who serve in the RAF have been wearing skirts since World War II, and were first allowed to wear trousers on parade 16 years ago.
The source said the uniform shake-up was designed to show the RAF as a "modern and inclusive employer" following a recent increase in trans recruits.
Women currently make up around 14% of the RAF’s personnel, which is higher than the proportion in either the Army or Royal Navy.