Hopefully, this clears the misconceptions for you...

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AI Overview

Yes, multiple foreign cash currencies were used to deliver a $1.7 billion payment to Iran in January 2016 as part of the JCPOA settlement because existing U.S. sanctions laws prohibited Iran from accessing the U.S. financial system, effectively blocking direct wire transfers in U.S. dollars.

The payment, which settled a long-standing dispute over a failed 1970s military sale, consisted of $400 million in principal and $1.3 billion in interest.

Key Details on the Cash Payments:
Currencies Used: The funds were converted into non-U.S. currencies, specifically Swiss francs, euros, and other foreign currencies, which were transported on pallets via cargo planes.

Reason for Cash: The U.S. Treasury Department confirmed the use of cash and non-U.S. currency was necessary because sanctions had isolated Iran from the international financial system. Specifically, U.S. sanctions barred Iran from making transactions that involved the U.S. dollar, prohibiting them from clearing payments through U.S. banks (the "U-turn" license was restricted).

Source of Funds: The money came from the taxpayer-funded Judgment Fund, which is used for legal settlements.
Logistics: The funds were procured from the central banks of the Netherlands and Switzerland before being transferred, according to reports.

While the JCPOA lifted nuclear-related sanctions and reconnected many Iranian banks to SWIFT, U.S. sanctions prohibiting direct or indirect access to the U.S. financial system remained in place, necessitating these alternative payment methods.
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