Theresa May has now signed a letter to trigger Article 50, the start of the official process to leave the EU.
Transport Safety Fears
New research suggests nearly half of women in London want to see women-only Tube and train carriages over fears about safety.
It also suggests around the same proportion of women in London don't feel safe on public transport.
Women-only rail carriages were last seen nearly forty years ago, but they're being talked about again about after the Transport Minister Claire Perry said in September 2014 that she was open to ideas that improved safety.
There's been a rise in reports of sexual offences being committed on public transport.
The poll asked nearly 6,300 women in 15 of the world's largest capital cities and New York if they would feel safer in single-sex areas on buses in trains.
"I think that it's incredibly insulting to the vast majority of men but it also failing female passengers not to tackle the problem at its root," said Laura Bates, founder of the antiharassment Everyday Sexism Project in London.
The world's largest capital, Tokyo, was one of the first, in 2000, to introduce women-only cars on trains to stop women being abused.
Julie Babinard, senior transport specialist from the World Bank, said women-only carriages were a short term fix and not a panacea for harassment of women.
"The emerging interest in several countries on women-only initiatives should be seen as an opportunity for improving security in cities but not as a silver bullet for dealing with gender-based violence in transportation and urban settings," Babinard told the Thomson Reuters Foundation.
"Women-only initiatives are not likely to provide long-term solutions as they only segregate by gender and provide a short-term remedy instead of addressing more fundamental issues."
Overall, London was ranked the fourth safest of the cities behind New York, Beijing and Tokyo, but ahead of Paris.
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