The Secretary is authorized under such rules and regulations as he may prescribe to pay as an interest subsidy on loans which are guaranteed or insured under the provisions of subchapter II of this chapter amounts which are necessary to reduce the rate payable by the borrower to the rate determined under section 1464 of this title.

There are authorized to be appropriated for fiscal year 1985, and for each fiscal year thereafter, an amount which does not exceed $5,500,000 for purposes of making interest payments authorized under this subchapter. Sums appropriated under this section, shall remain available until expended.