What is the ruling on eating meat sold in the markets of non-Islamic countries?

Scholars have agreed on the prohibition of the slaughtered animals of polytheists and deniers of religions. They have permitted the slaughtered animals of the People of the Book, but have differed regarding the slaughtered animals of the Magians (Zoroastrians). The four Imams and the majority of scholars have prohibited the slaughtered animals of the Magians, while others have permitted them, though this is a weak opinion. The prohibition is based on the Almighty Allah’s saying: (This day [all] good foods have been made lawful for you. And the food of those who were given the Scripture is lawful for you, and your food is lawful for them) Al-Ma'idah/5. The "food of those who were given the Scripture" refers to their slaughtered animals, and the implication of the verse is that the slaughtered animals of those other than the People of the Book are prohibited.

Therefore, meat in the markets of non-Islamic countries is permissible if it is known to be from the slaughtered animals of the People of the Book and it has not been proven that it was slaughtered in a way contrary to Islamic law. It is prohibited if it is from the slaughtered animals of disbelievers who are not from the People of the Book. Merely saying "Bismillah" (in the name of Allah) over it at the time of eating is not sufficient, for the hadith of Aisha that mentions saying "Bismillah" refers to Muslims who were new to Islam, not to disbelievers. The difficulty of obtaining halal meat in those countries does not permit eating what is prohibited, nor does it place the Muslim in the category of one in dire necessity.