Any challenge to action under 25 CFR part 163 taken by an approving officer or subordinate official exercising delegated authority from the Secretary shall be exclusively through administrative appeal or as provided in the Indian Self-Determination and Education Assistance Act (Pub. L. 93-638, as amended). Such appeal(s) shall be filed in accordance with the provisions of 25 CFR part 2, Appeals from administrative actions, except that an appeal of any action under part 163 of this title shall:
(a) Not stay any action unless otherwise directed by the Secretary; and
(b) Define “interested party” for purposes of bringing such an appeal or participating in such an appeal as any person whose own direct economic interest is adversely affected by an action or decision.