LGBT+ equality campaigners said the EHRC’s approach was “deeply troubling” and that it was “failing to stand up for equality for trans people”.

The EHRC told Shona Robison, minister in charge of the reforms, that “more detailed consideration” was required – despite the EHRC having made a supportive submission to a Scottish government consultation on its plans less than two years ago.

The government is planning to introduce a simplified system for transgender people to change their sex on their birth certificates by the end of February. Supporters of the move say the change would not affect the spaces transgender people use nor confer new rights on them.

The Scottish government said in response to the letter that “our support for trans rights does not conflict with our continued strong commitment to advance equality and to protect and uphold women’s rights”.

LGBT rights charity Stonewall said in a statement: “We are deeply troubled by the approach that the EHRC is taking to trans people’s human rights. Their approach appears to focus on pleasing a noisy minority of anti-trans activists, rather than promoting human rights for all LGBTQ+ people.”

The letter, sent from ECHR chair, Baroness Kishwer Falkner, to Ms Robison yesterday, stated that “some lawyers, academics, data users and others have increasingly expressed concerns about the potential implications of changing the current criteria for obtaining a Gender Recognition Certificate.

“The potential consequences include those relating to the collection and use of data, participation and drug testing in competitive sport, measures to address barriers facing women, and practices within the criminal justice system, inter alia.

“As such, we consider that more detailed consideration is needed before any change is made to the provisions in the act.”

A Scottish government spokesperson said: “We will consider the EHRC’s views, which have changed from their response to the 2019 consultation, along with those of others ahead of introduction of the bill.

“We appreciate the range of views on proposals to reform the Gender Recognition Act. We have always been keen to seek consensus where possible, and to work to support respectful debate, and will continue to do so.”