The Messenger of Allah ﷺ said, "A Muslim is not to be killed in retaliation for a disbeliever."Through the same chain of narration, the Prophet ﷺ said, "The blood-money for a disbeliever is half the blood-money for a believer."
حدثنا عيسى بن أحمد حدثنا ابن وهب عن أسامة بن زيد
أن رسول الله ﷺ قال لا يقتل مسلم بكافر وبهذا الإسناد عن النبي ﷺ قال دية عقل الكافر نصف دية عقل المؤمن
[Its chain of transmission is hasan]. Nasai also recorded it, 45/8, no. 4811 (Qasamah, chapter, How much is the blood money of a disbeliever) through the narration of Ibn Wahb, containing the first hadith. Abu Dawud, no. 4583, and Ibn Majah, no. 2644, recorded the second hadith. The hadith has corroborating narrations.