By Daphne Psaledakis WASHINGTON, June 22 (Reuters) - The United States authorized Iranian oil sales on Monday, easing decades-old sanctions as it pushes toward a final peace deal with Tehran in return for commitments on nuclear inspections and free transit through the Strait of Hormuz. The general license, announced by the Treasury Department, allows the sale of crude oil and petrochemical and petroleum products of Iranian origin through August 21.