Students at Exeter University have been warned that cross-dressing on nights out can be as offensive as blackening their faces.
The university's students guild has published an article which warns of the "crass and offensive" nature of both "blacking-up" and cross-dressing.
The article, published to mark diversity week, states that there are several "trans-identified" students at Exeter, and more who express their identity as "gender-queer", meaning that they reject gender roles.
It goes on: "To parody this appearance is crass and offensive on the same level as ethnicity; it implies a judgment of a gender or gender appearance as inferior and can be intensely psychologically damaging to anyone of student age."
The article states that the guild – the university's students' union – is not demanding an end to cross-dressing, but asking people to ensure that their behaviour is not "harming, insulting or mocking another student".
Exeter University student Clare Baars, said she was "disappointed" in the guild for "trying to control students' freedom of expression".
She said: "Are we to speak out against pirate fancy dress because it might offend people? Or having emergency services dress up socials because professionals in these fields might take it the wrong way? Surely not. The whole thing is ludicrous."
Yesterday, Nicky Stevens, a transgender regional organiser for the Beaumont Society, which offers support over transgender issues, said it was a "fine line" between having fun and mocking.
"Some people would certainly find it insensitive. Of course we do have a sense of humour and we understand that people don't want to be restricted in what they wear for a night out. If it's in the spirit of fancy dress it's usually not a problem, but some transgender men can't look feminine, no matter how hard they try.
"When it crosses the line into mocking them it's offensive."
Guild president Nick Davis said it had never received a complaint abut drag dressing from a transgender person, and was not out to "police fun" and has a "vibrant" student body with dressing up "part of the student experience".
But he said the union wanted to raise awareness of the potential for offence. He referred to the furore surrounding a rape joke on website UniLad, which involved a Plymouth University student.
Exeter University was also embroiled in a row about a joke which trivialised rape, and was published in a guild newsletter in November, for which it apologised.