LONDON (AP) — The British government said Monday it will block a new law making it easier for people in Scotland to legally change their gender, sparking a clash with transgender rights advocates and the Scottish nationalist administration in Edinburgh. .

Scotland’s Secretary of State Alister Jack said he would prevent the bill from gaining Royal Assent, the final formality that makes it law, out of concern it would conflict with «Britain’s equality legislation.» «. That legislation, among other things, guarantees women’s and girls’ access to single-sex spaces such as locker rooms and shelters.

The Scottish government is likely to challenge the decision in the UK Supreme Court.

Scottish First Minister Nicola Sturgeon called the decision by First Minister Rishi Sunak’s Conservative government «a frontal attack» on the Scottish Parliament, which passed the bill last month.

“The Scottish government will uphold the legislation and uphold the Scottish Parliament,” he said on Twitter. «If this Westminster veto is successful, it will be the first of many.»

The Scottish bill allows people over the age of 16 in Scotland to change the gender designation on their identity documents by self-declaration, removing the need for a medical diagnosis of gender dysphoria.

It also reduces the time trans people must live in a different expressed gender before the change is legally recognized, from two years to three months for adults and six months for 16- and 17-year-olds.

The legislation sets Scotland apart from the rest of the UK, where a medical diagnosis is needed before people can transition for legal purposes.

The Scottish National Party-led government in Edinburgh says the legal change will improve the lives of transgender people by allowing them to obtain official documents that match their gender identities.

Opponents say it risks allowing predatory men to gain access to spaces designated for women, such as shelters for survivors of domestic abuse. Others argue that the minimum transition age should remain at 18.

Scotland is part of the United Kingdom but, like Wales and Northern Ireland, has its own semi-autonomous government with broad powers in areas including healthcare.

This is the first time a UK government has blocked a Scottish law since the Scottish government and parliament were established a quarter of a century ago. The move will provide fodder for nationalists who want Scotland to break away from the UK and become an independent country.

Jack, the UK minister responsible for Scotland, said he had «not taken this decision lightly».

“Transgender people who are going through the process of changing their legal sex deserve our respect, support and understanding,” she said in a letter to Sturgeon. «My decision today is about the consequences of the legislation for the functioning of equality protections across the UK.»

Shami Chakrabarti, a member of the Labor Party in the House of Lords and a former head of the Liberty rights group, said Sunak’s government may be trying to provoke «culture wars» by intervening, but legally «they may be right».