Mo. Rev. Stat. § 65.670
Whenever the township planning commission has adopted, recorded and filed certified copies of any part of the official master plan relating to major highways or to subdivision regulations, thereafter no plat of a subdivision of land within the unincorporated area of such township or the portion thereof covered by the major highway plan shall be recorded until such plat shall first have been approved by the township planning commission. If the township planning commission does not report upon the plat within thirty days, it may then be deemed approved by the township planning commission, and the township planning commission shall certify such facts upon such plat. If such plat is approved by the township planning commission, such approval shall be endorsed in writing thereon. However, if such plat be amended or rejected by the township planning commission, such approval shall be deemed overruled. No plat of subdivision of land in the unincorporated areas of the county shall be recorded in the office of the recorder of deeds unless and until approved as provided in sections 65.650 to 65.700. Municipalities shall have power, by ordinance, to require plats of subdivision of land within the corporate limits of such municipalities to be submitted to the township planning commission before being submitted to the municipality for approval, and before being recorded. A certified copy of any such ordinance shall be filed in the office of the recorder of deeds for the county. The township planning commission shall, upon written request of any such municipality, consider such plats and shall report its findings and its recommendations thereon in writing to the proper officials of such municipality.
§ 65.670, RSMo