Musnad Abu Ya'la al-Mawsili 209:24

Abu Bakr narrated to us, Waki' narrated to us, from Dawud ibn Abi 'Abd Allah, from Ibn Jud'an, from his grandmother, from Umm Salamah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "There is no alliance (hilf) in Islam. And whatever alliance existed in the Pre-Islamic Period (Jahiliyyah), Islam has only increased it in strength."