FIRST Minister Nicola Sturgeon has said it would be an "outrage" if the UK Government blocks Scotland's gender reforms from becoming law.

Prime Minister Rishi Sunak is reportedly considering deploying a Section 35 order to stop the Gender Recognition Reform (Scotland) Bill from being given Royal Assent.

The UK Government has until Wednesday to make the move and risks sparking a constitutional row in the process.

The GRR Bill passed with cross-party support in Holyrood before Christmas, gathering support from MSPs in all five parties. 

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The FM was asked about the plans at a press conference on the NHS crisis on Monday, and said there were "no grounds" for the Tories to challenge the legislation as it is within Holyrood's competence. 

She added: "It doesn't affect the operation of the Equality Act, and it was passed by an overwhelming majority of the Scottish Parliament after very lengthy and very intense scrutiny by MSPs of all parties represented in the parliament.

"So if there is a decision to challenge, then in my view, it will be quite simply a political decision.

The National: Holyrood's gender reforms were passed by MSPs before ChristmasHolyrood's gender reforms were passed by MSPs before Christmas (Image: PA)

"And I think using trans people, already one of the most vulnerable stigmatised groups in our society as a political weapon, will be unconscionable and indefensible and really quite disgraceful."

The First Minister added that there is an "issue of principle" and the Scottish Parliament's right to legislate "within its areas of competence".

She said: "I would say to anyone who may welcome that because they disagree with this particular piece of legislation - if the UK government is able to normalise action to block legislation, democratically passed by the Scottish Parliament, within our areas of competence on this issue, then that will embolden them to look to do it on other issues and we will be on a very, very slippery slope indeed. 

"I think it is that serious, and I think the import and significance of this would go beyond the particular subject matter of the legislation."

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Sturgeon said she believes there are two routes the UK Government may take to block the legislation. The first is a Section 33 order which would require the bill to be taken to the Supreme Court, or a Section 35 order, allowing the Tory government to block the legislation under certain limited circumstances, which the Scottish Government can judicially review.

The FM added: "What I can say in general is that we will absolutely robustly and vigorously, and with a very high degree of confidence, defend the legislation."

It comes as Labour leader Keir Starmer faced a backlash from within his own party after he said he had "concerns" about Scotland's gender reforms.

Labour MSPs backed the reforms with the party whipping the vote, but Starmer told the BBC he had “concerns about the provision in Scotland, in particular the age reduction to 16 and in particular the rejection of our amendment in relation to the Equalities Act”.

The National: Starmer contradicted his Labour MSPs by stating he had 'concerns' over the reformsStarmer contradicted his Labour MSPs by stating he had 'concerns' over the reforms

The FM was asked about Starmer's comments, to which she said she wonders if there is "anything Keir Starmer is willing to stand up and be counted on in the face of Tory attacks".

She added: "This is legislation that was scrutinised and voted for by Keir Starmer’s own party in the Scottish Parliament.

"He'd be showing, if he backed any move by the Government to block this, he'd be showing utter contempt for his own Scottish party as well as the Scottish Parliament.

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"We'll see what happens this week, but there is no justification whatsoever for the action that has been talked about."

It comes as Starmer was confronted on LBC over his comments. He was asked by Amber, a trans woman living in Edinburgh, what he would say to Scottish Labour MSPs who voted for the reforms and had amendments passed.

Starmer replied: "Not all the amendments that they wanted went through and that troubles me.

"Obviously, as it went through the Scottish Parliament, it's a matter for Scotland and for Scottish Labour, but it now is becoming a UK-wide issue.

"The question now is whether or not the government should take action to interfere with the usual Royal Assent.

"So it's now moved down but from a  purely Scottish issue into a UK-wide issue and that's why it's very important I made my position clear."

Downing Street has said Scottish Secretary Alister Jack will make an announcement on whether to block Scotland’s gender laws ahead of Wednesday’s deadline.

The Prime Minister’s official spokesman said: “No decision has been taken at this point by the UK Government.

“It’s the Secretary of State for Scotland who is the ultimate decision-maker and you can expect to hear from him before the deadline on Wednesday.”