Notwithstanding the provisions of this chapter limiting the making and insuring of loans to citizens of the United States, the Secretary may make and insure loans under this chapter to aliens lawfully admitted to the United States for permanent residence under the Immigration and Nationality Act [8 U.S.C. 1101 et seq.]: Provided, That no loans may be made or insured under this chapter to such aliens until the Secretary issues regulations establishing the terms and conditions under which such aliens may receive loans: Provided further