UN special rapporteur on violence against women Rashida Manjoo said after visiting a number of cities, including Glasgow and Edinburgh, she found a "boys' club sexist culture." in Britain and said this influences perceptions of women and girls.
Ms Manjoo also warned Government cutbacks have hit violence-against-women services and confirmed reports she was blocked from entering controversial immigration detention centre for women, Yarl's Wood.
The South African human rights expert said legal and policy responses focused on harmful practices, such as early and forced marriages but ignored harm coming from a "a sexist culture that exists in the country".
She added: "Have I seen this level of sexist culture in other countries? It hasn't been so 'in your face' in other countries.
"I haven't seen that so pervasively in other countries. I'm sure it exists but it wasn't so much and so pervasive. I'm not sure what gives rise to a more visible presence of sexist portrayals of women and girls in this country in particular.
"What is clear from these indications of portrayals of women and girls is that there is a boys' club sexist culture"
Ms Manjoo said she had identified "isolated pockets of good practice", but these were still not practised consistently. She said many groups had raised the impact of austerity measures, adding that cuts were having a "disproportionate impact" on the provision of violence-against-women services.