observe veil. If there are no indications, then it is Mustaḥab for her to observe veil with these men. After the age of twelve, in particular, extra stress should be laid (on the observance of veil) because this age is close to puberty and to the full development of lust.
(Fatāwā Razawiyyaĥ, vol. 23, pp. 639)
Question: Do Islamic sisters have to observe veil with non-Muslim women too?
Answer: Yes! Islamic sisters have to observe veil with non-Muslim women just as they have to do with non-Maḥram men. The detail about this issue is that Islamic sisters must observe veil with non-Muslim women the same as with non-Maḥram men. That is, the fundamental ruling of Islamic jurisprudence is that it is necessary for an Islamic sister to hide her entire body from non-Maḥram men, except her visible beauty i.e. her face, palms, and feet below the ankles. However, according to ‘the latter scholars’ these three parts of her body should also be concealed from non-Maḥram men.
The rulings about a woman observing veil with non-Maḥram men have been explained in part 18, Sūraĥ An-Nūr, verse 31. The same blessed verse states the ruling about a Muslim woman observing veil with a non-Muslim woman. As the entire body of a Muslim woman – except ‘مَا ظَهَرَ مِنۡهَا’ what is apparent itself – is to be concealed from a non-Maḥram man, similarly, it is also to be concealed from a non-Muslim woman. This is clarified by the Holy Quran at the place of exception in words ‘اَوۡ نِسَآئِہِنَّ’ (the woman of their own religion). Allah عَزَّوَجَلَّ stated: