It is understood that finance director John Coke and enterprises director Jonathan Dutton, both appointed by Fisk, will also leave the CIM in June, before their one-year contracts come up for renewal.
The departures will leave the CIM without a senior management team and put a question mark over the future of many of the changes introduced by Fisk.
Fisk, who was appointed to the post in January 2003, inherited a raft of problems which have beset the CIM since it became a charity two years previously.
In its annual report and accounts to the end of June 2003, the CIM's International Board of Trustees said the Charity Commission had been alerted to issues that included the correct separation of non-charitable and charitable finances, membership activities being accounted for through the charity and payments made in error to three trustees for time spent on CIM activities.
It is understood the new structure has been designed to comply with Charity Commission regulations. However, a senior CIM source refused to rule out that it may give up its charitable status in future.
The proposed structure is very different from the one Fisk joined and establishes separate management teams for two commercial subsidiaries. The core charity body continues to be overseen by the IBT, and houses the CIM's academic, educational and research activities.
Fisk's agenda for change met vehement resistance in some CIM quarters. Ex-CIM chairman John Edmond has been seeking 200 signatories to call a meeting to propose a vote of no confidence in Fisk.
The CIM refused to confirm Fisk's resignation. Fisk declined to comment.
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