After any plan for major streets, or portions thereof, has been prepared and adopted by a city planning commission, the council shall be authorized and empowered to establish, regulate and limit building or setback lines on such major streets by ordinance and to prohibit any new building being located within the building or setback lines, and to amend such regulations from time to time.
Laws 1977, c. 256, § 47-121, eff. July 1, 1978.