The City Manager shall be ex officio purchasing agent for the city and may, in his discretion, designate a deputy under his direct control and supervision to perform the normal functions of the office of purchasing agent. The City Manager shall establish and maintain, by appropriate rules and regulations, an efficient and economical system for the purchasing of and contracting for such supplies, equipment and services as may from time to time be required by the city; provided, that such rules and regulations shall be approved by the City Council prior to promulgation and taking effect.
('69 Code, § 2-24)