Liz Truss is to propose a law that will ban children from trying to change their gender.
She also wants to ban transgender women from entering female-only spaces - including toilets, changing rooms, refuges and prisons.
Aides close to the former prime minister say she hopes to propose a Bill in the Commons this week that will prevent under-18s from accessing hormone therapy and block the state from recognising social transitioning by children.
The draft legislation will also aim to ensure single-sex spaces are protected in law. More specifically, it will prevent transgender women from accessing female-only areas.
A source said Ms Truss felt there needed to be stronger protections in law to prevent under-18s from “making irreversible decisions about their bodies which they might come to regret”.
They added: “In her time as minister for women and equalities, Liz successfully blocked dangerous plans to allow gender self-ID.
“It has become increasingly clear there is a need for the law to better protect children and teenagers from making irreversible decisions about their bodies which they might come to regret.
“The law also needs to be amended in order to make it clear that biological males should be legally excluded from having access to single-sex spaces designated for women, including toilets, changing rooms, refuges and prisons.
“Liz decided to put forward these proposals after considering the amount of correspondence she receives on these issues and taking soundings from her South West Norfolk constituents.
“These are not party political issues and she hopes to bring together a broad cross-party alliance in support of her Bill.”
But there is no guarantee her Bill will be debated in the Commons.
She was 18th among the 20 MPs selected to bring forward a private members' bill - which allows backbenchers to introduce a new law.
Normally, only the first seven bills will have time to be included in a day’s debate and therefore have the highest chance of becoming law.
The contents of the Bill will be formally presented to the Commons on Wednesday, along with a list of its MP backers.
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