31 C.F.R. § 560.521 Diplomatic pouches.
Title 31 - Money and Finance: Treasury
All transactions in connection with the importation into the United States from Iran, or the exportation from the United States to Iran, of diplomatic pouches and their contents are authorized.
Title 31: Money and Finance: Treasury
PART 560—IRANIAN TRANSACTIONS REGULATIONS
Subpart E—Licenses, Authorizations and Statements of Licensing Policy
§ 560.521 Diplomatic pouches.