Abu Sakinah (may Allah have mercy on him) narrates from a Companion (may Allah be pleased with him) of the Prophet (peace and blessings be upon him): "Leave the Abyssinians alone as long as they leave you alone, and leave the Turks alone as long as they leave you alone."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 18597