(a) We may disapprove a WSR lease amendment only if at least one of the following is true:

(1) The Indian landowners have not consented and their consent is required;

(2) The lessee's mortgagees or sureties have not consented;

(3) The lessee is in violation of the lease;

(4) The requirements of this subpart have not been met; or

(5) We find a compelling reason to withhold our approval in order to protect the best interests of the Indian landowners.

(b) We will defer, to the maximum extent possible, to the Indian landowners' determination that the amendment is in their best interest.

(c) We may not unreasonably withhold approval of an amendment.