Complaints over an advert for bookmaker Paddy Power featuring transgender people have been upheld by the Advertising Standards Authority (ASA).
The TV advert shown in February ahead of Ladies' Day at the Cheltenham Festival invited viewers to spot the "stallions" from the "mares".
The ASA investigated 92 complaints that the advert was offensive and condoned harmful discriminatory behaviour.
It ruled that it must not be shown again in its current form.
The advert stated: "...we're going to make Ladies' Day even more exciting by sending in some beautiful transgendered ladies. Spot the stallions from the mares".
The advert showed a series of brief shots of people at the event while the voice-over tried to guess their gender.
In one scene, a woman was shown holding a dog while the voice-over said "woman" then hesitated while the shot changed to show a woman walking out of a men's toilet, then said "dog, I mean man".
'Almost 600,000 views'
The ASA said it received about 470 complaints, but only 92 of those fell under their remit to investigate because the majority followed the advert being watched online rather than on television.
Upholding the complaints, the ASA said: "We considered that the ad trivialised a highly complex issue and depicted a number of common negative stereotypes about trans people.
"We considered that by suggesting that trans women would look like men in drag, and that their gender could be speculated on as part of a game, the ad irresponsibly reinforced those negative stereotypes.
"And, particularly by framing the game in a way that involved a member of the public who had commented on Paddy Power's Facebook page, the ad condoned and encouraged harmful discriminatory behaviour and treatment."
Paddy Power said that it did not intend to cause harm or offence and was "saddened" to learn that some viewers were offended.
It said it believed that the complaints had come from an organised campaign.
A Paddy Power spokesman said the company was disappointed with the ASA's ruling.
He added: "This decision is especially frustrating given that the commercial was pre-approved by British television advertising clearance body Clearcast, who then considered the humour in the advert, while not to everyone's taste, fell short of causing offence.
"Additionally, we reached out to leading UK transgender group, The Beaumont Society, for feedback on the script.
"Furthermore, we exclusively cast members of the trans community in the various transgender roles in the commercial.
"Finally, it is worth pointing out that the commercial has almost 600,000 views with twice as many 'likes' than 'dislikes."
The Beaumont Society told the ASA the script it was given did not include the scene in which a woman left a men's toilet and was referred to as a dog.
It also said that it was not happy with the manner in which the terms "stallions" and "mares" were used in the finished advert.
Какого черта здесь нужно Чатрукьяну? - недовольно поинтересовался Стратмор. - Сегодня не его дежурство. - Похоже, что-то стряслось, - сказала Сьюзан.