It is declared that the legislative intent of this act is to improve the safety and convenience of the highways of this state.
(1) It may be determined by the general assembly that funds shall be expended from the state road fund for the purposes of this act, or
(2) Any funds expended by the state hereunder as may be necessary to comply with any federal law or requirement which is or may become a condition to receipt of federal funds for highway purposes shall be appropriated only from state highway funds.