Pompeo claimed the campaign had succeeded with minimal impact on oil prices, noting that crude futures are sitting roughly where they were when the administration announced its Iran policy in May.
That assessment does not account for what has happened to oil prices between then and now, as well as in anticipation of the U.S. withdrawal from the nuclear deal.
In the month prior to Trump’s announcement, the cost of crude ran up about $7 a barrel, hitting 3½-year highs. Oil prices traded in a range until late September, when they began a rally to four-year highs as traders braced for oil shortages following the sanctions.
Prices have since backed down to their lowest since April following a punishing October sell-off in global financial markets, weakening oil demand forecasts and increases in output from OPEC, the United States and Russia.
International benchmark Brent crude is up 9 percent this year, while U.S. crude is up nearly 5 percent, with the sanctions playing a major role in the rally. Higher crude costs have heaped financial pain on oil importing countries with weakening currencies, including India, Argentina and Turkey.
Mnuchin said the list of blocked entities will total roughly 700 when the final sanctions information is released on Monday. That includes hundreds that were granted sanctions relief under the 2015 nuclear deal, as well as roughly 300 additional entities.
The Treasury secretary also sought to clarify the U.S. position on SWIFT, the financial messaging system that facilitates transactions around the world.
Mnuchin said SWIFT could be subject to sanctions if the system facilitates transactions for designated Iranian financial institutions. The United States is telling SWIFT to disconnect any of those designated institutions as soon as possible, he added.
The SWIFT system will be allowed to facilitate transactions with non-designated entities for certain humanitarian goods like medicine and food, Mnuchin said. However, he warned that the United States would sanction banks that facilitate illicit transactions masquerading as humanitarian trade.