أَخْبَرَنَا هَارُونُ بْنُ مُحَمَّدِ بْنِ بَكَّارِ بْنِ بِلاَلٍ، عَنْ مُحَمَّدِ بْنِ عِيسَى، - وَهُوَ ابْنُ سُمَيْعٍ - قَالَ حَدَّثَنَا حُمَيْدٌ الطَّوِيلُ، عَنْ أَنَسِ بْنِ مَالِكٍ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏"‏ أُمِرْتُ أَنْ أُقَاتِلَ الْمُشْرِكِينَ حَتَّى يَشْهَدُوا أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ وَأَنَّ مُحَمَّدًا عَبْدُهُ وَرَسُولُهُ فَإِذَا شَهِدُوا أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ وَأَنَّ مُحَمَّدًا عَبْدُهُ وَرَسُولُهُ وَصَلَّوْا صَلاَتَنَا وَاسْتَقْبَلُوا قِبْلَتَنَا وَأَكَلُوا ذَبَائِحَنَا فَقَدْ حَرُمَتْ عَلَيْنَا دِمَاؤُهُمْ وَأَمْوَالُهُمْ إِلاَّ بِحَقِّهَا ‏"‏ ‏.‏

It was narrated from Anas bin Malik that: The Prophet [SAW] said: "I have been commanded to fight the idolators until they bear witness to La ilaha illallah (there is none worthy of worship except Allah) and that Muhammad is His slave and Messenger. If they bear witness to La ilaha illallah and that Muhammad is His slave and Messenger, and they pray as we pray and face our Qiblah, and eat our slaughtered animals, then their blood and wealth becomes forbidden to us except for a right that is due." Translation Not Available

Book Ref: Sunan An Nisai Book 37 Hadith 3966
Web Ref:  Sunan An Nisai Vol 5 Book 37 Hadith 3971