It was originally due to start in January, before being moved back to June 3.

French media are now reporting it is due to begin on June 8, one day after Diack's 87th birthday, although the exact reason for the further delay is unknown.

Diack, who led the IAAF from 1999 to 2015, is charged with "giving and receiving bribes", "breach of trust" and "organised money laundering" and is facing a potential 10-year prison sentence for allegedly taking bribes to cover up tests showing doping by 23 Russian athletes, as reported by France 24.

Prosecutors allege Diack, who was arrested in November 2015, obtained $1.5 million (£1.2 million/€1.36 million) of Russian funds to help fund Macky Sall's successful campaign for President of Senegal in 2012, in exchange for the IAAF's anti-doping arm covering up offences by Russian athletes.

The trial will take place in Paris and is expected to last 10 days, as reported by L'Equipe.

Papa Massata Diack, son of Lamine, is one of five other defendants in the case.

In their order for reference, the magistrates in charge of the investigation estimated that "Papa Massata Diack could only be enriched in considerable proportions to the prejudice of the IAAF with the constant and enlightened support of his father, who cannot leave the sole responsibility for it to his son."

In the same document, judges say Diack "played an active role, abusing his quality as President of the institution, and effectively placed his son at the heart of the system put in place which enabled him to divert important upstream revenues from the IAAF funds."

Four other defendants will also be tried in the case - Gabriel Dollé, former director of the IAAF's medical and anti-doping department, Habib Cissé, lawyer and ex-legal advisor to Lamine Diack, Valentin Balakhnichev, ex-President of the Russian Athletics Federation (ARAF) and former treasurer and vice-president of the IAAF and Alexei Melnikov, former head coach of long distance races at ARAF.

Only Lamine Diack, Dollé and Cissé are expected to be present at the opening of the trial.

Papa Diack, who lives in Senegal, is under an international arrest warrant issued on February 13 by French judicial authorities, while Balaknichev and Melnikov are also the subject of arrest warrants, however both the Senegalese and Russian Governments are refusing to extradite the accused.

The trial was originally due to begin on January 13 but was adjourned just hours before it was due to start after prosecutors asked for more time to review three folders worth of documents relating to evidence given by Papa Diack in November.