Sforno on Deuteronomy 2:10/ספורנו על דברים ב׳:י׳

1האימים לפנים, seeing that the descendants of Lot had no legal claim to inherit anything from Avraham at all, G’d announced that He had given them ancestral land just as He had done to the descendants of Esau who were descended from Avraham in a straight line. G’d testifies that both the Ammonites and the Moabites came to possess what they owned contrary to accepted norms.