No such local improvement shall be undertaken by any municipality where objections thereto in writing are filed with the municipal clerk, before the final passage of the ordinance, by the owners of two-thirds in value of the lands proposed to be assessed for benefit as determined by the governing body, who shall use for that purpose the last preceding valuation for the purpose of taxation.

If, however, the governing body shall determine such local improvement to be a public necessity they may undertake the same notwithstanding such objections, subject to the provisions of section 40:49-25 of this title.