Nothing in this title prohibits the Secretary, after execution of the Agreement, from approving any modification to the Agreement, including an attachment to the Agreement, that is consistent with this title, to the extent that the modification does not otherwise require congressional approval under section 2116 of the Revised Statutes ( 25 U.S.C. 177 ) or any other applicable provision of Federal law. (c) Environmental compliance (1) In general In implementing the Agreement and this title, the Secretary shall comply with— (A) the Endangered Species Act of 1973 ( 16 U.S.C. 1531 et seq. )