(a) With regard to any real property loan originated or to be originated by a Federal savings association, as a matter of contract between it and the borrower, a Federal savings association continues to have the power to include a due-on-sale clause in its loan instrument.

(b) Except as otherwise provided in § 191.5 of this part with respect to any such loan made on the security of a home occupied or to be occupied by the borrower, exercise by any lender of a due-on-sale clause in a loan originated by a Federal savings association shall be exclusively governed by the terms of the loan contract, and all rights and remedies of the lender and borrower shall at all times be fixed and governed by that contract.