Prime Minister Boris Johnson says it seems “sensible” that transgender women should not be able to compete in female sporting categories.

Johnson made the comments during a visit to a hospital in Welwyn Garden City on Wednesday in the wake of transgender cyclist Emily Bridges being prevented from riding at the National Omnium Championships in Derby last weekend.

Bridges, who began hormone therapy last year, had been due to race for the first time in the female category after British Cycling gave the 21-year-old the green light to enter, but the International Cycling Union ruled her ineligible.

“I don’t think that biological males should be competing in female sporting events. And maybe that’s a controversial thing… but it just seems to me to be sensible,” the Prime Minister said.

“That doesn’t mean that I’m not immensely sympathetic to people who want to change gender, to transition. It’s vital that we give people the maximum possible love and support in making those decisions.

“But these are complex issues and I don’t think they can be solved with one swift, easy piece of legislation. It takes a lot of thought to get this right.”

Welsh rider Bridges detailed how she had been “harassed and demonised” in the days after UCI had prevented her from racing at the Derby Velodrome Arena.

She first went public with the challenges she has faced with her gender at the end of 2020 and, while going through hormone therapy, has continued to race in men event’s, winning the men’s points race at the British Universities Championships in Glasgow in February.

Stonewall criticised the intervention of cycling’s world governing body and insisted they were disappointed Bridges had not been given a “fair chance” despite being in full compliance of British Cycling’s competition criteria, with her testosterone levels below five nanomoles per litre for the past 12 months.

“As is no surprise with most of the British media, I’ve been relentlessly harassed and demonised by those who have a specific agenda to push,” Bridges wrote on social media on Friday.

“They attack anything that isn’t the norm and print whatever is most likely to result in the highest engagement for their articles, and bring in advertising.

“This is without care for the wellbeing of individuals or marginalised groups, and others are left to pick up the pieces due to their actions.”

Bridges continued: “Despite the public announcement, I still have little clarity around their finding of my ineligibility under their regulations.

“I am an athlete, and I just want to race competitively again, within the regulations set by British Cycling and UCI after careful consideration of the research around transgender athletes.

“No one should have to choose between being who they are, and participating in the sport they love.”

The Prime Minister’s comments come after a letter to the UCI signed by a group of elite female cyclists, as well as Sara Symington, the head of Olympic and Paralympic programmes at British Cycling, called for stronger regulation on the matter.

The signatories said it was a matter of “deep regret” that a “crisis situation” around the National Championships had prompted the world governing body to step in and therefore concede its current rule was “probably not enough”.

“Recently, female athletes in the UK have shown you that they were willing to boycott their own National Championship to get the UCI and British Cycling to hear their concerns about fairness in their sport,” the letter read. “That is how seriously female athletes are taking this issue.”

The letter branded the UCI’s currently ruling “discriminatory in that it advantages only biological male athletes” and called for the body to “rescind” it immediately, unless it could provide “robust scientific evidence” that it “guarantees fairness”.

It added that the UCI should “implement eligibility criteria for the female category that is based on female biological characteristics”.

Stonewall, the LGBTQ+ rights charity, issued a fresh statement following Wednesday’s comments by the Prime Minister.

A spokesperson said: “Trans people deserve the same opportunities as everyone else to enjoy the benefits of sport and blanket exclusions on trans people participating are fundamentally unfair.

“This is a complex and fast-evolving issue and much of the science doesn’t yet exist in this area. Inclusion policies need to be considered on a sport-by-sport basis and it’s vital to avoid using inflammatory rhetoric, which often causes trans people to stop playing the sports they love.

“While elite sport often dominates these discussions, it only makes up a tiny proportion of all sport played in the UK. We know that trans people are also under-represented in community sport and often feel excluded.

“Two in five trans people (38 per cent) say they avoid going to the gym or participating in sports groups because they fear of discrimination and harassment. Sport has the unique power to bring us together and it’s important that trans people have the opportunity to enjoy the benefits of sport without facing exclusion or abuse.”