June 12, 2011.Iraq raised the July prices for its Basrah Light crude oil to customers in all markets. The discount for Basrah Light crude to the U.S. narrowed to $2 less than the Argus Sour Crude Index, making the oil 10 cents a barrel more expensive than in June. Persian Gulf producers sell most of their crude to refiners under long-term contracts. Most regional state-run oil companies price their crudes at a premium or discount to a benchmark.