According to the International Professional Practices Framework (IPPF) issued by the Institute of Internal Auditors (IIA), the internal audit charter must be formally approved by senior management and the board.
This requirement ensures that the internal audit activity has the appropriate authority, support, and independence to carry out its responsibilities effectively. The charter defines the purpose, authority, and responsibility of the internal audit activity, providing a clear framework for its operations and ensuring alignment with the organization's objectives and governance structures.
References:
* The IIA Standards: Standard 1000 - Purpose, Authority, and Responsibility: "The purpose, authority, and responsibility of the internal audit activity must be formally defined in an internal audit charter, consistent with the Definition of Internal Auditing, the Code of Ethics, and the Standards. The chief audit executive must periodically review the internal audit charter and present it to senior management and the board for approval."