edict
noun
oil exploration is prohibited by government edict:
decree, order, command, commandment, mandate, proclamation, pronouncement, dictum, dictate, fiat, promulgation, precept;
law, statute, act, enactment, bill, ordinance, regulation, rule, ruling, injunction, manifesto;
in Tsarist Russia ukase;
in Spanish-speaking countries pronunciamento;
rare firman, decretal, irade, rescript.
edict Oxford Dictionary of English