Iran produces about 4 million barrels of oil a day, most of which it exports. The country imports nearly all of its refined petroleum products — such as gasoline and diesel fuel — from Europe and India.
“And I think the thing that would bring the Iranian government and economy to its knees, quite quickly, would not be a cut-off of their exports of unrefined petroleum (but to ban) their imports of refined petroleum products,” [former CIA Director James] Woolsey said.

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