All meetings of public bodies of the City shall be open to the public, except as allowed by the laws of Ohio or as Council may further provide by ordinance or resolution for matters declared in such ordinance or resolution to require confidentiality, including but not limited to, obtaining general legal advice from the public body's attorney and matters of a competitive nature relating to any City owned or operated utility. Except as herein provided, only the public body calling an executive session and its invited guests may attend such executive session. The Mayor shall not be excluded from an executive session of Council.