In addition to any other authority that the Secretary may have to defer principal and interest and forego foreclosure, the Secretary may permit, at the request of the borrower, the deferral of principal and interest on any outstanding loan made, insured, or held by the Secretary under this chapter, or under the provisions of any other law administered by the Farmers Home Administration or by the Rural Development Administration, and may forego foreclosure of any such loan, for such period as the Secretary deems necessary upon a showing by the borrower that due to circumstances beyond the borrower’s control, the borrower is temporarily unable to continue making payments of such principal and interest when due without unduly impairing the standard of living of the borrower. The Secretary may permit interest that accrues during the deferral period on any loan deferred under this section to bear no interest during or after such period: Provided, That if the security instrument securing such loan is foreclosed such interest as is included in the purchase price at such foreclosure shall become part of the principal and draw interest from the date of foreclosure at the rate prescribed by law.