; and (iii) use the services of the Department of Housing and Urban Development on a reimbursable basis, and the Secretary of Housing and Urban Development is authorized to provide services as requested by the Secretary of Treasury using all authorities vested in or delegated to the Department of Housing and Urban Development. (2) Transfer of amounts to Treasury Such portions of the appropriation to the Secretary of Housing and Urban Development shall be transferred by the Secretary of Housing and Urban Development to the Department of the Treasury from time-to-time in an amount equal to, as determined by the Secretary of the Treasury in consultation with the Secretary of Housing and Urban Development, the amount necessary for the purchase of securities under the Program during the period for which the funds are intended to be available. (3) Use of proceeds Revenues of and proceeds from the sale, exercise, or surrender of assets purchased or acquired under the Program under this section shall be available to the Secretary of the Treasury through September 30, 2033, for purposes of purchases under subsection (b)(1)(B)(i). (c) Limitation on aggregate loan insurance or guarantee authority The aggregate original principal obligation of all covered mortgage loans insured or guaranteed under subsection (e)(1)(A) of this section may not exceed $48,000,000,000, and under section (e)(1)(B) may not exceed $12,000,000,000. (d) GNMA guarantee authority and fee To carry out the purposes of this section, the Government National Mortgage Association may enter into new commitments to issue guarantees of securities based on or backed by mortgages insured or guaranteed under this section, not exceeding $60,000,000,000, and shall collect guaranty fees consistent with section 306(g)(1) of the National Housing Act ( 12 U.S.C. 1721(g)(1) ) that are paid at securitization. (e) Definitions In this section: (1) Covered mortgage loan (A) In general The term covered mortgage loan means, for purposes of the Program established by the