The UK Government has confirmed it will “robustly defend” its decision to block Scotland’s controversial gender reforms ahead of a looming court battle.

Ministers in Westminster previously moved to prevent the Gender Recognition Reform Bill, which was passed by MSPs in December, from becoming law.

Scottish secretary Alister Jack used a section 35 order – a never-before-utilised part of the Scotland Act – to stop the legislation from gaining royal assent.

The UK Government previously moved to block Scotland's controversial gender reforms

First Minister Humza Yousaf described this as an “undemocratic veto”, and last month the Scottish Government announced it would seek a judicial review over the decision.

The UK Government argues the move was necessary because the legislation, which simplifies the process trans people go through to obtain legal recognition in their preferred gender, would have an impact on Great Britain-wide equality laws.

One legal figure told The Scotsman a bill of £500,000 was possible if the court battle goes all the way to the UK Supreme Court, as is widely expected.

MSPs voted to pass the Gender Recognition Reform Bill by 86 votes to 39 before Christmas. The legislation lowers the age that people can apply for a GRC from 18 to 16, and also removes the need for medical reports.

However, it has sparked huge controversy, with concerns from some politicians, women’s rights groups and others the changes could impact on safe spaces for females.

The final days of the Bill’s passage were marred by two mammoth Scottish Parliament sittings, with MSPs debating amendments into the early hours of the morning, and a number of protests within the Holyrood chamber.

A UK Government spokeswoman said: “The UK Government will robustly defend the Secretary of State’s decision to prevent the Scottish Government's Gender Recognition Reform Bill from becoming law. We are clear that the proposed legislation would have an adverse effect on reserved matters, including on the operation of the law as it applies to Great Britain-wide equalities protections.”

The Advocate General for Scotland, representing Mr Jack, has informed the Court of Session the UK Government intends to contest the petition for judicial review, should the court decide to grant permission to proceed.

In its petition to the court, the Scottish Government said Mr Jack made a “material error of law”, that his concerns about the safeguards in the Bill were “irrelevant” to the order’s making, and that his reasons were “inadequate”, which would make the order “unlawful”.

Last month, Lord Sumption, a former Supreme Court judge, said the Scottish Government’s case would be "very difficult" to win. He said: "I think that the Scottish Government's legal position is arguable, but I think it is weak."

Speaking to journalists in Holyrood, Mr Yousaf rejected suggestions his Government was wasting money on the legal challenge. He said: “We’re, of course, engaged in this court process because I’m not prepared to accept a Westminster veto over legislation that’s passed by a majority. I’ll not say much more, of course, because we have engaged in court proceedings.”

Conservative MSP Rachael Hamilton said: “Rather than redraft a flawed Bill – that puts the safety of women and girls at risk – Humza Yousaf has opted to ignore the views of the majority of Scots, who are opposed to it, and embark on another unwanted and unnecessary court case.

“It’s a nakedly transparent attempt to manufacture grievance with the UK Government to try to divert attention from the civil war and scandal engulfing the SNP.”

UK Government to 'robustly defend' decision to block Scotland's controversial gender reforms

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