Within 96 hours after the adjournment of any Council meeting, the City Clerk shall present to the Mayor the record of proceedings of the meeting and all ordinances and resolutions adopted at the meeting. The Mayor, within seven days of receipt of an ordinance or resolution, shall return it to the City Clerk with or without his approval, or with his veto. If an ordinance or resolution is vetoed, the Mayor shall attach a written statement explaining the reasons for his veto. Ordinances and resolutions vetoed by the Mayor shall be considered at the next regular meeting of the Council, and the Council may pass the ordinance or resolution over the veto by the affirmative vote of not less than four-fifths of its members. The Mayor's veto power shall extend to disapproving or reducing individual appropriation items in the budget or any ordinance or resolution, except appropriations for auditing or investigating any part of the executive branch. When the Mayor returns an ordinance or resolution to the City Clerk without his approval and without his veto within the seven day period, the ordinance or resolution shall become effective as though he had approved its passage.