A senior tax expert has lost her job at an international think tank over comments made about transgenderism on Twitter.

Maya Forstater made a series of seemingly straightforward comments about gender, which caused her to lose her job at the Centre for Global Development.

Among the comments were statements such as “yes I think that male people are not women. I don’t think being a woman/female is a matter of identity or womanly feelings. It is biology. People of either sex should not be constrained (or discriminated against) if they don’t conform to traditional gender expectations.”

In another tweet, Ms Forstater wrote, “what I am so surprised at is that smart people who I admire, who are absolutely pro-science in other areas, and champion human rights & womens [sic] rights are tying themselves in knots to avoid saying the truth that men cannot change into women (because that might hurt mens [sic] feelings).”

She also said that Karen White — a biologically-male ‘trans woman’ who was jailed for violent crimes and rape and was moved to a man’s prison after sexually assaulting fellow female inmates — was a “man” and spoke out about the danger to women if men are allowed to self-identify and have this used as the legal standard as it could lead to more women being harmed.

However, Ms Forstater’s employer said in an email to her that “You stated that a man’s internal feeling that he is a woman has no basis in material reality. A lot of people would find that offensive and exclusionary.”

Ms Forstater later said that despite her success with the organisation, her role was not renewed, leading to her losing her livelihood. According to The Times, she is believed to be the first person in Britain to lose her job for saying that trans women were not women.

Defending her comments, Forstater wrote in an article for Medium, “I have a definition of woman — adult human female. It does not come with any expectations or requirements for gendered behaviour. It is clear, well understood & critical for women rights including the right to spaces without male bodies. Why ditch this for something undefinable?”

Adding that “yes people should of course be able to define their identity any way they like. But other people are not compelled to accept it as relating to any material reality.”

She also stressed that “I support transgender people’s human rights and I believe that trans people are vulnerable, but no one group should overrerule others. I lost my job for speaking up about women’s rights, in a careful way and in a tone of ordinary discussion and disagreement. I worked for a think tank and I thought you ought to be able to think and talk about things. I found out I was wrong about that.”

She was defended by Jodie Ginsberg of Index on Censorship who said, “From what I have read of her writing, I cannot see that Maya has done anything wrong other than express an opinion that many feminists share — that there should be a public and open debate about the distinction between sex and gender.”

Mr Forstater is now launching a crowdfunding campaign to fund her legal defence against her previous employer.