Pioneers of the gay rights movement in Britain have discussed forming a breakaway organisation from the Stonewall pressure group because they fear women and children are at risk from its transgender policy.

In a letter to The Sunday Times, 22 signatories including Simon Fanshawe, who co-founded Stonewall in 1989, said it had “undermined women’s sex-based rights and protections”. They are most worried primary school children are too quickly challenged to review their gender identity.

They state: “If Stonewall remains intransigent, there must surely now be an opening for a new organisation committed both to freedom of speech and to fact instead of fantasy.” It has the working title LGB Alliance.

Their intervention is timed to put pressure on the government as it prepares to