Oil sales, ransoms and extortions help ISIS “generate tens of millions of dollars” monthly, the US Treasury estimates, promising to undermine the group’s finances and to impose sanctions on anyone attempting to do business with the extremists.

The Islamic State (IS, formerly ISIS/ISIL) has “amassed wealth at an unprecedented pace” and is now “probably the best-funded terrorist organization” the US has confronted, according to Treasury undersecretary for terrorism and financial intelligence, David Cohen.

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The bulk of the group’s wealth comes from oilfields in Syria and Iraq that are under the IS control, with oil sales earning the group “approximately $1 million a day,” the official said on Thursday, speaking at the Carnegie Endowment for International Peace.



The vice-president for the Endowment, Marwan Muasher, said the Islamic State is now "considered the world's wealthiest and most financially sophisticated terrorist organization," AFP reported.



The US Treasury has been determined to undermine the terror group’s sources of finance, but acknowledged the task is a challenging one.



“We have no silver bullet, no secret weapon to empty ISIL’s coffers overnight. This will be a sustained fight, and we are in the early stages,” Cohen said.

The official specified that the IS was selling oil at lower-than-market prices to various middlemen, including those from Turkey.



“It also appears that some of the oil emanating from territory where ISIL operates has been sold to Kurds in Iraq, and then resold into Turkey,” Cohen said.



He has also lashed out at Damascus over a possibility of it cooperating with the IS.



“And in a further indication of the [President Bashar] Assad regime’s depravity, it seems the Syrian government has made an arrangement to purchase oil from ISIL.”

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Washington is ready to impose economic sanctions on whoever it finds is engaged in doing business with the IS.



“The middlemen, traders, refiners, transport companies, and anyone else that handles ISIL’s oil should know that we are hard at work identifying them, and that we have tools at hand to stop them,” Cohen warned.



“We not only can cut them off from the US financial system and freeze their assets, but we can also make it very difficult for them to find a bank anywhere that will touch their money or process their transactions,’ he added.



In September, analysts interviewed by AP, estimated the IS could have been getting about $25 to $60 per barrel for its smuggled oil, compared to about $100 market price at that time.



The total profit of the extremist group was then estimated at $3 million a day by Luay al-Khatteeb, a visiting fellow at the Brookings Institution's Doha Center in Qatar.



An October report by IHS, a US-based consulting group, estimated that the IS was making up to $2 million per day, or $800 million a year, by selling oil on the black market before the US-led airstrikes.