Quran 9:12 — Ultimatum (Bara'ah)

If they violate their oaths after pledging to keep their covenants, and attack your religion, you may fight the leaders of paganism—you are no longer bound by your covenant with them—that they may refrain.

[9:11] If they repent and observe the Contact Prayers (Salat) and give the obligatory charity (Zakat), then they are your brethren in religion. We thus explain the revelations for people who know.

[9:13] Would you not fight people who violated their treaties, tried to banish the messenger, and they are the ones who started the war in the first place? Are you afraid of them? GOD is the One you are supposed to fear, if you are believers.