31 CFR §560.317

The term credits or loans means any transfer or extension of funds or credit on a basis of an obligation to repay, or any assumption or guarantee of the obligation of another to repay an extension of funds or credit, including but not limited to: Overdrafts; currency swaps; purchases of debt securities issued by the Government of Iran; purchases of a loan made by another person; sales of financial assets subject to an agreement to repurchase; renewals or refinancings whereby funds or credits are transferred to or extended to a prohibited borrower or prohibited recipient; the issuance of standby letters of credit; and drawdowns on existing lines of credit.