Jan 4 (Reuters) - Endeavour Mining said on Thursday it had removed CEO Sebastien de Montessus with immediate effect, citing "serious misconduct".

The action followed an investigation by the board into an irregular payment instruction of $5.9 million issued by him in relation to an asset disposal by the company.

The London-listed company also disclosed that allegations were made against him last year relating to his personal conduct with colleagues on its confidential whistleblowing channel.

Endeavour named Ian Cockerill, deputy chair of its board, as the new CEO.

Sebastien de Montessus, who was also removed as president and from the board of directors, did not immediately respond to a request for comment. (Reporting by Shivani Tanna in Bengaluru; Editing by Shilpi Majumdar and Sriraj Kalluvila)