Donald Trump 's administration has told the Supreme Court that transgender workers are not protected by federal civil rights law and can be fired because of their gender.

The US government is arguing workers should only be protected from discrimination based on their “biological sex”, court filings have revealed.

A Supreme Court ruling in favour of the administration’s position would set a legal precedent, marking a major setback for LGBTQ rights since the Obama administration.

The court filing relates to an upcoming court case involving transgender funeral home worker Aimee Stephens, who was fired from her job after telling her employer about her transition.

“In 1964, the ordinary public meaning of 'sex' was biological sex. It did not encompass transgender status,” the document filed on Friday reads.

Protesters hold baby Trump balloons in the rally outside of the president's 2020 campaign launch in Orlando, Florida

A member of the Proud Boys, a fascist group, holds a sign up outside of the president's 2020 campaign launch in Orlando, Florida

A baby blimp rises behind a group of anti-Trump protesters outside the president's campaign launch in Orlando, Florida

Supporters of Donald Trump face off against protesters outside of the president's 2020 campaign launch in Orlando, Florida

An anti-Trump protester calls for the president to be impeached outside the launch event for his 2020 campaign launch in Orlando, Florida

President Trump addresses supporters at the launch event of his 2020 election campaign in the Amway Centre in Orlando, Florida

Numerous baby Trump balloons are raised in protests outside of the president's 2020 campaign launch in Orlando, Florida

Members of the Proud Boys, a fascist group, jeer at anti-Trump protesters outside of the president's 2020 campaign launch

An anti-Trump protester faces off against a supporter outside the president's campaign launch in Orlando, Florida

A Proud Boy jeers at anti-Trump protesters who are separated from the president's supporters by a police line outside the president's campaign launch in Orlando, Florida

A Proud Boy shouts across the police line at anti-Trump protesters outside the president's campaign launch in Orlando, Florida

A Trump supporter faces off against a protester outside the president's campaign launch in Orlando, Florida

A protester dressed as a caricature of Donald Trump stands outside the president's 2020 campaign launch in Orlando, Florida

A line of police officers separate opposing groups of protesters outside the launch of President Trump's 2020 campaign launch

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President Trump addresses supporters at the launch event of his 2020 election campaign in Orlando, Florida

A baby blimp rears its head amidst a group of anti-Trump protesters outside the president't campaign launch in Orlando, Florida

Members of the Proud Boys, a fascist group, jeer at anti-Trump protesters outside of the president's 2020 campaign launch in Orlando, Florida

“Title VII [of the act] does not prohibit discrimination against transgender persons based on their transgender status,” the filing argues. “It simply does not speak to discrimination because of an individual’s gender identity or a disconnect between an individual’s gender identity and the individual’s sex.”