If a referendum petition, or amended petition, be found sufficient by the City Clerk he shall certify that fact to the Council at its next regular meeting and the ordinance or part thereof specified in the petition shall not go into effect, or further action thereunder shall be suspended if it shall have gone into effect, until approved by the electors as hereinafter provided. Upon receipt of the Clerk's certificate the Council shall proceed to reconsider the ordinance or part thereof, and its final vote upon such reconsideration shall be upon the question, "Shall the ordinance (or part of the ordinance) set forth in the referendum petition by repealed?" If upon such reconsideration the ordinance, or part thereof, be not repealed it shall be submitted to the electors at the next succeeding regular or general election held not less than thirty days after such final vote by the Council. The Council by vote of not less than all of the members elected to Council less two may submit the ordinance, or part thereof, to the electors at a special election to be held not sooner than the time aforesaid. If when submitted to the electors any ordinance, or part thereof, be not approved by a majority of those voting thereon it shall be deemed repealed.