British Cycling will prevent riders who were born male from racing in elite female events under a new transgender and non-binary participation policy.
The governing body's new rules for competitive events, due to be implemented later this year, will see racing split into "open" and "female" categories, with transgender women, transgender men, non-binary individuals and those whose sex was assigned male at birth eligible to compete in the open category.
The female category will remain for those whose sex was assigned female at birth, and transgender men who are yet to begin hormone therapy.
The current men's category will be consolidated into the open category, in which those whose sex was assigned as female at birth can also compete if they so wish.
British Cycling suspended its previous policy last April amid controversy after transgender woman Emily Bridges sought to race at the national omnium championships as a female rider.
The new policy change ends Bridges' hopes of competing in women's competitions.
Bridges questions her future in cycling: Policy is a 'violent act'
In a statement on Instagram, Bridge called the policy a "violent act", accused British Cycling of "furthering a genocide against us" and said the "racing scene was dying" under the organisation's stewardship.
She also suggested she was contemplating leaving the sport, writing: "I don't even know if I want to race my bike any more. The danger and everything that would come with racing makes it a pretty hard thing to justify to myself. But you have no right telling me when I am done. This is my decision and mine alone.
"I might be speaking strongly at the moment but this is my reality right now. It is literally a fight for survival for me and my family at the moment."
Bridges also said: "I agree there needs to be a nuanced policy discussion and continue to conduct research, but this hasn't happened. Research isn't being viewed critically, or any discussion about the relevance of the data to specific sports.
"Any discussion is inherently political and driven by bad faith actors. I've given my body up to science for the last two years, and this data will be out soon. There is actual, relevant data coming soon and discussions need to be had."
British Cycling declined to respond to Bridges' statement.
It is 14 months since the 22-year-old was barred from competing in her first women's event in Derby - facing five-time Olympic champion Dame Laura Kenny - after cycling's world governing body ruled she was not eligible to race because she was still registered as a male cyclist.
British Cycling chief: This is about being inclusive for all
Asked if the new policy is discriminatory, British Cycling chief Jon Dutton told Sky News: "We have taken a view that this is absolutely about being inclusive for all.
"We have taken consultation and listened to riders from across the cycling community, looked at the available medical research and taken the view from a legal perspective.
"We've created a new open category that anyone has the ability to ride in and also a non-competitive policy that is absolutely inclusive and accessible. We will not tolerate any form of discrimination in moving forward with this policy.
"It's really important that we support, we empathise, we are compassionate to the riders that are affected by this policy change."
Bridges, who set a national junior men's record over 25 miles in 2018, came out as a transgender woman in October 2020 and began hormone therapy last year to reduce her testosterone levels.
Dutton added: "Emily, and a number of athletes are clearly affected by this policy but we wanted to provide at this point in time is clarity on the direction of travel. The decision that we've made on behalf of British Cycling is for the whole of the cycling community."
Mr Dutton said: "It is very difficult. It's divisive. It's emotive. It's affecting human beings. And we absolutely fully understand and appreciate that. So it has been a difficult process."
British Cycling is emulating British Triathlon, which announced plans last year for an "open category" for men, transgender women and non-binary athletes.
International athletics and swimming governing bodies have banned athletes who underwent male puberty from competing in international women's events.
Cycling's global governing body is reviewing its rules after negativity provoked by Austin Killips, who is a transgender woman, winning the Tour of the Gila stage race in a women's race in New Mexico last month.