1. The regional planning commission may designate one or more joint planning areas in the comprehensive regional plan.
2. If an area is designated a joint planning area, the county and the affected cities shall jointly adopt a master plan for the area.
3. The master plan for a joint planning area must:
(a) Be consistent with the comprehensive regional plan;
(b) Designate the portion of the area, if any, that is included within the sphere of influence of a city;
(c) Designate the portion of the area, if any, that is subject to the jurisdiction of the county for planning and zoning and development decisions; and
(d) Be submitted to the regional planning commission for review pursuant to NRS 278.028.