Okla. Stat. tit. 12A § 5-115
An action to enforce a right or obligation arising under this article must be commenced within one (1) year after the expiration date of the relevant letter of credit or one (1) year after the cause of action accrues, whichever occurs later. A cause of action accrues when the breach occurs, regardless of the aggrieved party's lack of knowledge of the breach.
Okla. Stat. tit. 12A, § 5-115
Oklahoma Code Comment
Revised Section 5-115 for the first time imposes a one-year statute of limitations on LC actions, measured from the later of the expiration date of the LC or the accrual of the cause of action. The former version of Article 5 did not provide a limitations period for claims under LCs. Accordingly, claims for wrongful dishonor and breach of warranty under LCs have been subject to the five-year statute of limitations applicable to contract actions generally. See 12 Okla. Stat. § 95 (First). The new statute of limitations applies to all claims made under revised Article 5, including claims for which there are remedies under revised Section 5-111 . However, the shorter one-year period applies only with respect to LCs issued on or after the effective date of revised Article 5 (i.e., January 1, 1997). See the Introductory Oklahoma Commentary preceding revised Article 5.