Papa Massata Diack, an IAAF marketing consultant with exclusive rights to sell sponsorship in developing regions, stood down from his role last December.

It followed claims he had requested a $5 million (£3 million/€4.5 million) payment - $440,000 (£285,000/€400,000) of it in cash - from Qatar during the race to host the 2017 IAAF World Championships in October 2011.

Papa Massata Diack has denied the allegations but the matter was referred to the IAAF Ethics Commission.

The British newspaper which published the original documents has refused to provide any information to the inquiry, which is being led by Sir David Calvert-Smith, the former Director of Public Prosecutions of England and Wales.

Papa Massata Diack has now written to members of the IAAF's ruling Council to once again protest his innocence and calling for the inquiry to be closed. 

"It is clear that these those press allegations have now become an ethics violation investigation without any evidence to support the formal accusations made against my person," the Senegalese wrote in the letter, a copy of which has been obtained by insidethegames. 

"Far be it from me to blame the media in these circumstances as I admire the work they do in promoting athletics and understand it is their job to report on information that is passed on to them.

"The question is why such allegations are made at the very time of political change at the IAAF.

"Through the defamation of an African sports executive, who happens to be called Diack is not there an attempt to attack indirectly the President of the IAAF?

"Is not there an attempt to undermine the integrity of a man who has dedicated his life to promoting the universality of athletics and will be leaving a strong legacy of unversality, at grassroots level, the IAAF Diamond League in 3 continents and for elite track and field through the commercial programme that runs until 2029.

"To those who criticize me for being President Lamine Diack's son, I will answer that indeed he is my father, a man for whom I have tremendous admiration for being one of the first African sports administrators to lead sport globally. 

"He is my father, but during our professional relationship he has always treated me as he did with any other member of the IAAF team."

Lamine Diack is due to stand down next month as President of the IAAF after 16 years in the role.

The two candidates to replace him are Britain's Sebastian Coe, the two-time Olympic 1500 metres gold medallist, and the Ukraine's Sergey Bubka, the multiple world pole vault record holder.

The election is due to take place on August 19. 

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