A deal would help pave the way to ease sanctions against Tehran. U.S. benchmark crude oil lost $2.37 to $60.78 per barrel. Brent crude, the international standard, gave up $2.32 to $63.70 per barrel.

Read full article: Iran and US conclude a fourth round of negotiations over Tehran's nuclear program in Oman Iran and the United States have held a fourth round of talks over Tehran’s rapidly ...