According to an Islamic ruling based on a hadith reported by Hazrath Huzaifa RA the Prophet Muhammad SAW said that the whole earth has been made a place of prostration and its soil has been made pure for Muslims. This shows that all places are considered pure except where there is impurity. Islamic scholars explain in this fatwa that if a non Muslim place does not have any impurity and the place is clean then it is allowed to offer prayer there with permission. This Islamic ruling is supported by the hadith mentioned in Sahih Muslim 522 and explained in the Shafi fiqh reference Al Bayan 2 104.