Mont. Code Ann. § 7-14-4608

Either or both such resolutions referred to in 7-14-4606 and 7-14-4607 may be adopted by the legislative body of a city. If both such resolutions are adopted, they shall clearly specify areas within the city, less than the whole thereof, within which or projects over which the commission and the city, respectively, are to have jurisdiction and control. The division of such jurisdiction and control shall be as so specified but may be changed from time to time by action of both the legislative body and the commission to such extent as may be consistent with obligations to bondholders assumed under this part.