The Prime Minister has supported the decision of the International Swimming Federation (FINA) to keep men out of women’s competitions.
Boris Johnson said he agreed with the change of policy – announced last week – which excludes men who have gone through puberty from competing against women.
On Tuesday, Culture Secretary Nadine Dorries also endorsed FINA’s ban and urged UK sporting bodies to introduce similar policies.
When asked about FINA’s decision to protect women’s swimming, Mr Johnson said: “I haven’t studied it in detail but I see no reason to dissent.”
In reply to the question ‘can a woman have a penis’, he responded: “Not without being a man.”
The Prime Minister was also asked whether he thought there was a difference between a woman and someone who is biologically male but chooses to live as if a woman, to which he replied: “Yes”.
Earlier this week, Nadine Dorries told representatives from 15 sporting bodies that “elite and competitive women’s sport must be reserved for people born of the female sex”.
She said: “In the interests of sporting integrity, we must bring clarity to protect the future interests of sport around the world.”
In response, some groups said that they are “actively carrying out their own scientific research to establish the impact of athletes’ sex at birth and gender reassignment on athletic performance”.
Writing in the Mail on Sunday ahead of the meeting, Dorries commended FINA for its decision to make women’s sport fairer and safer. She declared: “Finally, reason seems to be returning to the world of sport”.
Elsewhere, the International Rugby League has temporarily barred men from the women’s game while it reviews its transgender policy.
And the Union Cycliste Internationale (UCI) has tightened its entry requirements for women’s events on the basis of testosterone levels.