In those sanctions programs with blocking authorities, OFAC's regulations block all "property" or "interests in property" in which a blocked person has an interest. The term "property" is very broadly defined, including present, future, or contingent interests. (For more information, see FAQ 9.)
For example, if a bank receives payment instructions from a customer to send a wire transfer to a blocked person, the bank should block the funds and report to OFAC through the OFAC Reporting System (ORS) within 10 business days from the date that property becomes blocked by the bank. For additional details on reporting, and to register for access to the ORS, please see the OFAC Reporting System page on OFAC's website.
However, if a customer simply asks a question such as, "Can I send money to Cuba?" then the bank can answer the customer's question or direct the customer to contact the OFAC Compliance Hotline for guidance.
The same logic applies to situations involving prohibited transactions that do not involve any blockable interest that must be rejected under OFAC sanctions regulations. If a bank receives instructions to send funds to a non-blocked person in Iran, then the bank must reject the transfer and file a reject report through ORS, pursuant to 31 CFR § 501.604. If a customer merely asks whether they can send funds to Iran and the bank explains that activity is prohibited, there is nothing to reject. In that situation, the bank does not need to file a report of a rejected transaction.