The various terms and provisions hereof, including the amount of medical assistance paid hereunder, are intended to comply with and give effect to the program set out in title XIX of the federal Social Security Act. During any period when federal funds shall not be available or shall be inadequate to pay in full the federal share of medical assistance as defined in title XIX of the federal Social Security Act, as amended by Public Law 92-603, the state may reduce by an amount equal to such deficiency the payments it would otherwise be obligated to make pursuant to section 256B.041.