The Irish Traveller Movement in Britain has described the condemnation of two adverts for Channel 4's Big Fat Gypsy Wedding as a "stunning victory" and attacked the broadcaster as "morally bankrupt".
However, ITMB chief executive Yvonne MacNamara called on those responsible for the ads to issue a full apology after the Advertising Standards Authority ruled that the adverts were offensive and irresponsible in a partial reversal of a decision earlier this year.
Four posters for the documentary, which originally drew 372 complaints, featured the words "Bigger. Fatter. Gypsier" over an image of a young boy looking directly at the camera and others of two teenagers wearing low-cut bra tops and three young girls dressed for their first Holy Communion standing in front of a caravan.
In February the ASA judged that although the adverts "might not be to everyone's taste", they were unlikely to cause serious or widespread offence as they reflected the content of the programme.
But an independent review recommended that the ASA reinvestigate the campaign following the request by the ITMB which had complained that the ads racially demeaned them and exposed their children to bullying and abuse.
Defending the campaign, Channel 4 said it centred on using real and intimate photographic portraits of gypsy and traveller life "in a style to reflect the journalistic intent of the series".
Informed consent had been obtained from all subjects or their relevant parent or guardian and final copies of the ads sent to all the families involved, with no objections.
But the ASA, which took advice from the Equality and Human Rights Commission, found that the ads featuring the young boy and the teenagers wearing low-cut tops could enforce prejudicial views against the gypsy and traveller community and were likely to cause serious offence to some members.
It also ruled that Channel 4 acted irresponsibly by depicting a child - one of the two young teenagers pictured in low-cut tops - in a sexualised way.
It found that two other ads showing a man leading a horse across a field with caravans in the background and the three young girls dressed for Holy Communion did not breach the advertising code.
The ASA said: "We noted that the boy in the image was shown in close-up and had his lips pursed in a manner that we considered was likely to be seen as aggressive.
"We considered that negative image, when combined with the strapline which suggested that such behaviour was "Gypsier", would be interpreted by many members of the gypsy and traveller communities and some of the wider public to mean that aggressive behaviour was typical of the younger members of the gypsy and traveller community.
"We considered that implication was likely to cause serious offence to some members of those communities while endorsing the prejudicial view that young gypsies and travellers were aggressive."
It said of the ad featuring the two teenagers: "We understood that the photo was an accurate depiction of how the young women had chosen to dress for the occasion at which they had been photographed and we considered that it was clear that they were dressed for a night out.
"However, we noted that they were heavily made-up and wearing low cut tops and we considered that, when combined with the strapline and in particular the word "Gypsier", the ad implied that appearance was highly representative of the gypsy and traveller community in a way that irresponsibly endorsed that prejudicial view and was likely to cause serious offence to the gypsy and traveller community."
It said that Channel 4 "acted irresponsibly" because the girl on the right of the poster was 15 when the picture was taken.
It ruled that the two ads must not appear again.
A Channel 4 spokesman said: "It was not Channel 4's intention for these adverts to cause offence but we are sorry this was the case among some members of the Gypsy and Traveller community.
"All responsible action was taken pre-publication. The posters were voluntarily submitted to the industry's independent CAP copy advice team who advised that they believed they complied with the advertising code, consent was obtained from contributors, and the posters were shared with those featured, who had no objections."
But MacNamara deamnded more from Channel 4, saying: "This is a stunning victory for Travellers and Gypsies. The ASA has condemned Channel 4's advertising campaign for the appalling harm it has done to the mental and moral wellbeing of Gypsy and Traveller children.
"The ITMB applaud the decision.. Channel 4's Big Fat Gypsy brand has been held up to be morally bankrupt.
"In its evidence to the ASA investigation, the Equalities and Human Rights Commission described anti-Gypsy and Traveller racism as the last respectable racism. The ASA has today made clear that it is no longer acceptable.
"The ITMB and the Gypsy and Traveller co-complainants call upon those responsible for these adverts to issue a full apology for the harm they have caused.
"If the billboards are likely to stir up prejudice and are harmful to children, then what are the implications for the TV shows that they advertise?"