'Allied with' in the Bible

Someone escaped, arrived, and reported what had happened to Abram the Hebrew, who was living by the oaks belonging to Mamre the Amorite, whose brothers Eshcol and Aner were allied with Abram.

I will take nothing except what my warriors have eaten. But as for what belongs to the men who were allied with me, including Aner, Eshcol, and Mamre, let them take their share."