12 CFR § 614.4720 - Letters of credit.
Banks for cooperatives and agricultural credit banks, under policies adopted by their boards of directors, may issue, advise, or confirm import or export letters of credit in accordance with the Uniform Commercial Code, or the Uniform Customs and Practice for Documentary Credits, to or on behalf of its customers. In addition, as a matter of sound banking practice, letters of credit shall be issued in conformity with the list which follows.
(a) Each letter of credit shall be in writing and shall conspicuously state that it is a letter of credit, or be conspicuously entitled as such.
(b) The letter of credit shall contain a specified expiration date or be for a definite term.
(c) The letter of credit shall contain a sum certain.
(d) The bank's obligation to pay should arise only upon fulfilling the terms and conditions as specified in the letter of credit. The bank must not be called upon to determine questions of fact or law at issue between the account party and the beneficiary.
(e) The bank's customer should have an unqualified obligation to reimburse the bank for payments made under the letter of credit.
(f) All letters of credit shall be irrevocable.