Two free schools due to open in Coventry will have "a detrimental impact on the city", according to a teaching union.
Jane Nellist, from Coventry National Union of Teachers (NUT), said the Seva Sikh school and a Muslim secondary school could increase segregation.
Supporters say faith as a way of life, rather than a belief, is hard to teach in existing local authority schools.
The council backs the schools and says they will be monitored.
The two institutions, which have started recruiting pupils and are due to open next September, will be the first free schools in Coventry.
The Muslim Coventry Leadership Academy for Girls said it would aim for a balance of 50% Muslim and 50% non-Muslim pupils. The Sikh Seva School Coventry said it was hoping for a 50% Sikh intake. [BBC] Read more