South Africa's Finance Minister Nhlanhla Nene looks on ahead of the Judicial Commission of Inquiry probing state capture in Johannesburg, South Africa October 3, 2018. REUTERS/Siphiwe Sibeko

JOHANNESBURG (Reuters) - South Africa’s Finance Minister Nhlanhla Nene is due to give evidence on Wednesday at an inquiry into influence-peddling, testimony that could reveal new details about the role of former president Jacob Zuma and his friends, the Guptas.

Nene is a pivotal figure in a probe into the three Indian-born Gupta brothers, who built a business empire during Zuma’s nine-year tenure only to see it disintegrate as the scandal-plagued leader was forced out by his own party in February.

The Gupta family and Zuma have denied any wrongdoing and say the allegations are part of an orchestrated witch hunt.

Zuma fired Nene in December 2015 and replaced him with largely unknown lawmaker Des van Rooyen, sending markets into a tailspin before Zuma appointed investor-friendly Pravin Gordhan as his third finance minister in the space of four days.

Nene has never given details about a dramatic period that revealed to global investors for the first time what was at stake in a battle within the ruling African National Congress over the influence of the Guptas.

Zuma’s successor as president Cyril Ramaphosa re-appointed Nene finance minister in February this year.

The long-awaited inquiry into allegations the Guptas used ties to Zuma to win billions of rand’s worth of government contracts opened last month with witnesses testifying that the brothers had tried to bribe them or had threatened them.

Deputy Chief Justice Raymond Zondo leads the public inquiry, which is empowered to make recommendations for prosecutions.