Prominent Australian writer and broadcaster Catherine McGregor, who was previously the most senior transgender military officer in the country, has hit out at president Donald Trump's decree that transgender people can no longer serve in the US military.

In a series of tweets on Wednesday, Trump said the military "cannot be burdened" by the "tremendous medical costs and disruption" of transgender people serving.



There is great uncertainty about the immediate ramifications of the tweets, and the White House has indicated it currently has no plan for what to do about the thousands of transgender people already serving in the US military.