If any municipality shall, pursuant to the authority of this chapter, incorporate into its corporate boundaries property situated in a county other than the county in which the principal office of the municipality is located, it shall not thereafter extend its boundaries into such other county, without, in addition to complying with all existing laws of this state governing or relating to the extension of corporate boundaries of municipalities, first obtaining the consent and approval of the board of supervisors of such county into which it desires to extend its corporate boundaries.
