Twitter is banning women from speaking out against the 'dangerous dogma of trans ideology', claim a group of angry feminists.

Fair Play for Women published an open letter to Martha Lane Fox, who sits on the company's board, to back their right to 'not be shamed or silenced' for speaking about their views.

The women claim Twitter accounts are being deleted for 'simply stating basic, incontrovertible biological facts', such as men are not women.

The feminist group say by banning them from the site after such statements, Twitter is carrying out 'a concerted attack on women's free speech'.

Fair Play for Women published an open letter to Martha Lane Fox, who sits on Twitter's board, to back their right to 'not be silenced' for speaking out against the 'dogma of trans ideology'

The women claim Twitter accounts are being deleted for 'simply stating basic, incontrovertible biological facts', such as 'women give birth'

The feminist group claims by banning them from the site after such statements, Twitter is carrying out 'a concerted attack on women's free speech'

They hope Ms Fox, who is also a member of the House of Lords, will help 'stop allowing men to police our language, threaten us and abuse us'.

Mail Online has contacted Twitter for a comment.

A portion of the open letter reads: 'We are liberal minded women, committed to women's rights, and social justice. We have fought for reproductive rights, gay rights, spent our lifetimes speaking up for women and against male violence and working to change the systems and structures that oppress us.

'Feminists also use Twitter to speak about another issue that threatens to erode not only our hard won rights, spaces and services, but the very definition of who we are. Transactivism.

'This misogynistic, aggressive, violent movement, that has been embraced by the hard Left as the latest civil rights cause, has seen males colonise womanhood and hijack feminism for its own purposes.'

Fair Play for Women say women have been 'threatened with violence' for saying things that 'should not be controversial, but have become so'.

They hope Ms Fox (pictured), who is also a member of the House of Lords, will help 'stop allowing men to police our language, threaten us and abuse us'

Fair Play for Women say women have been 'threatened with violence' for saying things that 'should not be controversial, but have become so'

This includes 'saying that males cannot become females. For saying that women do not have penises. For saying that women's spaces such as refuges should be safe havens for women only,' according to the group.

The letter adds: 'Not only that, women are being told that to talk about their biology is transphobic. That we must refer to ourselves as menstruators, uterus havers, pregnant people.

'This is a concerted attack on women's free speech. The words we use to describe ourselves, our bodies, our biology and our experiences as women are becoming unsayable.'

Transsexual writer Miranda Yardley said she was blocked from using Twitter after writing that Green Party LGBT member Aimee Challenor, a trans woman, is a man, according to the BBC.

Ms Yardley said: 'According to the rules of Twitter it is now hateful conduct to call someone who is a man, a man.

'The implication of this is that the concept of proscribed speech, things we are now not allowed to say, now extends to the truth. This is fundamentally illiberal.'

Trans activist Ashleigh Talbot hit back at the letter, saying it was stoking 'hatred against trans and non-binary people by calling us dangerous'.

She told the BBC that there are often anti-trans attack pieces in the media, and the community is 'small and vulnerable' and their free speech is often diminished.