19 U.S.C. § 4084: Articles exempt from relief

The President may not provide import relief under this part with respect to any article if—(1) import relief previously has been provided under this part with respect to that article; or (2) the article is subject to import relief under—(A) part A; or (B) chapter 1 of title II of the Trade Act of 1974 [19 U.S.C. 2251 et seq.].