The Democratic Alliance has requested Public Protector Busisiwe Mkhwebane to investigate Finance Minister Nhlanhla Nene.
The party wants Mkhwebane to determine whether Nene has breached the executive code of ethics and exposed himself to a conflict between his offcial responsibilities and private interests.
The request is related to allegations surrounding a Public Investment Corporation investment in S&S Refinarias of Mozambique.
This reportedly included a $1.7 million referral fee which may have benefited the minister’s son, Siyabonga Nene.
The party says that the Public Protector’s Office has confirmed that its Good Governance and Integrity Branch will investigate the matter.
This comes amid growing pressure for Nene to leave office after he admitted to holding earlier meetings with the Gupta family.
However, the Treasury has confirmed that he will travel to Indonesia for a meeting of the International Monetary Fund on Wednesday, suggesting he will not leave office immediately.
There have been widespread calls for Nene to resign or for President Cyril Ramaphosa to fire him.
Reports have suggested that an announcement on Nene’s future could be made shortly.