The notices carry no legal force; station staff and police can only firmly ask male passengers to leave

They are supposed to be a safe haven in the rush hour, where women and girls can escape the “gropers” who haunt Japan’s trains. But women-only railway carriages are under assault from men who say that their human rights are being violated.

Women’s groups are calling for the provision of single-sex compartments to be written into law after protests by the Association Opposing Women-Only Carriages.

The men say that the carriages are discriminatory and imply that all men are potential sexual harassers.

Despite low crime rates in Japan, sexual assault is prevalent on public transport. In surveys, two in three young women have reported being groped. The first women-only carriages were introduced in 2001. Polls show that three in four women and two in three