A commission of inquiry will investigate whether President Jacob Zuma played any role in the Gupta family’s alleged offer of cabinet posts to people including former deputy finance minister Mcebisi Jonas and other claims that they influenced state decisions.

The inquiry will be guided by the report of the nation’s former public protector, Thuli Madonsela, according to its terms of reference published in the Government Gazette on Thursday. She ordered the inquiry into allegations that the Guptas may have influenced cabinet appointments and received special treatment for a coal business linked to the family and one of the president’s sons. Zuma and the Guptas have denied wrongdoing.

Jonas said the Gupta family offered him the position of finance minister, two months before Nhlanhla Nene was removed from the post, sparking a drop in the rand and the nation’s bonds.

Last month, deputy President Cyril Ramaphosa succeeded Zuma as head of the ANC and has pledged to clamp down on corruption in a bid to revive the ruling party’s flagging public support before general elections next year and boost investor confidence in the economy.

Some senior members of the ANC have called for the commission to probe allegations of undue influence over state decisions going back as far as 1994 and beyond, under the former all-white government. The terms of reference may be expanded or amended, according to the proclamation.

Madonsela said in November 2016 that chief justice Mogoeng Mogoeng should appoint the head of the inquiry because the president had a conflict of interest.

Zuma said earlier this month he would appoint the commission and abide by a court ruling that Mogoeng must select its leader. This was after the high court in December rejected Zuma’s arguments that he alone can set up the commission and ordered him to pay the cost of the case. Zuma accepted Mogoeng’s recommendation that his deputy, Raymond Zondo, head the commission.