With the approval of the Department of Transportation, the payment of the principal and interest on bonds issued for construction or improvement of township or district roads or grade separations located within the road district. If the road district desires to use motor fuel tax funds for this purpose it shall follow the same procedure in expending moneys secured in the creation of the indebtedness as if the construction or improvement was to be paid for directly with motor fuel tax funds under the provisions of Section 6-701.1 of this Code.