39 U.S.C. § 5403
The Postal Service may impose or remit fines on carriers transporting mail by air on routes extending beyond the borders of the United States for—
(Pub. L. 91–375, , 84 Stat. 773.)
Section effective , pursuant to Resolution No. 71–9 of the Board of Governors. See section 15(a) of Pub. L. 91–375, set out as a note preceding section 101 of this title.