All territory hereafter annexed into the City of Kenedy, Texas, shall be classified as "A" Agricultural District, until permanently zoned by the city council of the City of Kenedy. The planning and zoning commission may, after annexation of any territory into the City of Kenedy, institute proceedings on its own motion to give newly annexed territory a permanent zoning, and the procedure to be followed shall be the same as is provided by law for the adoption of original zoning regulations.