ENOfficial
One of the Prophet's companions said: Let the Abyssinians alone as long as they let you alone, and leave the Turks alone as long as they leave you alone. Abu Dawud and Nasai transmitted it.
Source: sunnah.com
Other translations
Arabic
وَعَنْ رَجُلٌ مِنْ أَصْحَابِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «دَعُوا الْحَبَشَةَ مَا وَدَعُوكُمْ وَاتْرُكُوا التُّرْكَ مَا تَرَكُوكُمْ» . رَوَاهُ أَبُو دَاوُدَ وَالنَّسَائِيّ
sunnah.com