Mujahid (may Allah have mercy on him) said: A Muslim woman should not take off her head-covering in the presence of an idolatrous woman, nor kiss her, because Allah Almighty said: "or their women" [Surah al-Nur: 31], and these (disbelieving women) are not their women.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 13544