It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "Hatred of Banu Hashim and the Ansar is disbelief, and hatred of the Arabs is hypocrisy."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 11264