Energy Minister Jeff Radebe announced on Tuesday that he had removed the suspended director and CEO of the Nuclear Energy Corporation of SA, Phumzile Tshelane.
In a brief statement, Radebe said he had taken the decision based on the "serious nature of the charges" Tshelane was facing, along with a board resolution and a recommendation by a disciplinary panel.
His removal was effective May 11, he said.
"The Necsa board will soon embark on the advertising and recruitment process to fill the vacant position in the board with individuals with appropriate skills and expertise to guide the company going forward and ensure sustainability and growth of the Necsa Group," Radebe said.
Radebe has previously flagged serious governance issues at Necsa. In December, he replaced the entire board due to failures to exercise its fiduciary duties.
Necsa conducts research and development in the field of nuclear energy, radiation sciences and technology. It is also responsible for uranium enrichment.
At a press conference at the time, Radebe said Tshelane had been placed on precautionary suspension and an investigation was underway into allegations of irregularities. He said a disciplinary process would follow pending the initial investigation.
Radebe said then that Don Robertson, a former managing director of a subsidiary of Necsa, NTP, had been appointed interim CEO.