Iran riches coveted by Big Oil after decades of conflict

As Iran and the U.S. enter 11th-hour negotiations to reach a nuclear deal and ease sanctions, the Middle Eastern country is re-emerging as a potential prize for Western oil companies such as BP, Royal Dutch Shell Plc, Eni SpA and Total SA. The Chinese can also be expected to enter the race, while U.S. companies, more burdened by sanctions and legacy, will be further down the pack.