The Alba Party’s Holyrood leader has tabled a motion aiming to scrap controversial gender reforms after a judgment said the blocking of the Bill was lawful.

The Gender Recognition Reform (Scotland) Bill was passed by MSPs last December, but blocked by the UK Government using Section 35 of the Scotland Act over fears it could have an impact on reserved areas.

Following an appeal by Scottish ministers, the Court of Session ruled on Friday that Scottish Secretary Alister Jack’s usage of Section 35 was lawful, giving First Minister Humza Yousaf three weeks to decide on an appeal of the decision.

Mr Yousaf said the judgment was a “dark day” for devolution.

Ash Regan – who recently defected from the SNP – has already urged the First Minister to abandon the plans, along with fellow former party leadership candidate Kate Forbes.

On Monday, Ms Regan announced she has tabled a motion at Holyrood calling for the plans to be dropped.

“Hundreds of thousands of pounds have already been wasted and it would be unimaginable for the Scottish Government to appeal this decision and then ultimately proceed to a situation of potentially asking the UK Supreme Court to overturn a decision of Scotland’s highest court,” she said.

“I resigned from the Government as I simply could not support legislation that is so ill thought-out, opposed by women’s groups across Scotland and a fundamental risk to the safety of women and girls.

The Scottish Government lost the battle in court and they will further lose the support of the people of Scotland if they keep pursuing this policy

“The Scottish Government lost the battle in court and they will further lose the support of the people of Scotland if they keep pursuing this policy.

“I urge Humza Yousaf to now completely scrap his Government’s gender reforms.”

If enacted, the reforms would have made it easier for transgender people to gain a gender recognition certificate (GRC), by lowering the required age from 18 to 16 and reducing the length of time required to live in one’s acquired gender.

The plans would also allow for self-identification, meaning a doctor’s diagnosis of gender dysphoria would not be required to obtain a GRC.

The legislation received support from all parties in Holyrood last year, passing by 86 votes to 39 following a mammoth final stage which included MSPs sitting until the early hours of the morning on two straight days to consider amendments.