Two of the schools are in Monmouthshire, three are in North-East Wales and five are in Pembroke-shire. "The reasons why the schools were given special dispensation in 1991 may no longer be as compelling," Mr Hain said this week.
The White Paper Building Excellent Schools Together, published in July, made it clear that all pupils in Wales should be given the chance to learn the language, spoken by about one in five people in Wales.
At one of the 10 schools, Monmouth comprehensive, head David Every said circumstances had not changed since exemption was granted. "There's not been a Welsh speaker in the school since 1970."