Rishi Sunak has boasted about blocking the Scottish Parliament's gender reform legislation.
The Prime Minister told Piers Morgan on Thursday evening it was "bold" for the UK Government to use a Section 35 order to prevent the Gender Recognition Reform (Scotland) Bill from becoming law.
He also suggested it was one of the most important things he had done in his first 100 days as Prime Minister.
Scotland Secretary Alister Jack said last month the bill had been blocked because it affected the UK-wide Equalities Act.
This was the first time a Section 35 order had been used to strike down an act of the Scottish Parliament since it was founded in 1999.
Sunak told Piers Morgan on Talk TV: "We can and will have compassion and tolerance and understanding for everybody who is thinking about transitioning and changing their identity or gender.
"But you know, for me, when it comes to whether it's sex, whether it's women's spaces, whether it's prisons, biological sex really matters.
"And actually we saw that recently with what’s going on in Scotland and that's why I took, again, you say what else have you done in 100 days and what’s bold?
"We took action that hadn’t been taken before because the bill that was passed in Scotland, I think has real implications for how we think about these issues on a UK-wide basis and the interaction between these things, particularly on women’s safety.
"And that’s why I acted."
The Gender Recognition Reform (Scotland) Bill would have removed the need for a medical diagnosis of gender dysphoria to obtain a gender recognition certificate ( GRC ).
It also would have lowered the minimum age for applicants to 16 and drops the time required for an applicant to live in their acquired gender from two years to three months – six for those aged 16 and 17 – though with a three-month reflection period.
The Bill was voted through the Scottish Parliament with support from members of all parties.
To sign up to the Daily Record Politics newsletter, click here.