Suspended Eskom chief financial officer (CFO), Anoj Singh, resigned on Monday, South Africa's power utility said.

"Eskom has today [on Monday] received, through Anoj Singh’s attorneys, a formal letter of resignation by Singh from his position as the Chief Financial Officer, in line with the terms of his employment contract," Eskom said in statement.

"The board of Eskom, through the Chairman, has accepted the resignation and communicated the acceptance through Singh’s attorneys. Singh’s resignation is with immediate effect."

On Saturday, the Presidency announced that Phakamani Hadebe has been appointed Eskom acting chief executive officer (CEO) with immediate effect, while Jabu Mabuza will take over as chairman of the board, and all Eskom executives facing allegations of serious corruption and other acts of impropriety, including Matshela Koko and Singh, would immediately be removed.

"The new board had also been instructed to appoint a permanent group chief executive officer and a group financial officer within the next three months," the presidency said in a statement at the time.

A number of measures were being taken to to "strengthen governance" at Eskom, including the appointment of new board members and stabilising management at the energy parastatal, it said.

This followed a meeting of President Jacob Zuma, Deputy President Cyril Ramaphosa, Public Enterprises Minister Lynne Brown, and Finance Minister Malusi Gigaba on Friday to address urgent problems at the company. This intervention would be ratified by Cabinet at its next meeting.

"Eskom is critical to the South African economy. As a key enabler of economic growth and social transformation any further deterioration of Eskom’s financial and operational conditions could have a severe impact on the country," the presidency said.

Eskom had been facing several problems, including a weak financial position, declining revenues, and governance failures, which threatened the sustainability of the company in future.

Therefore, government had decided on immediate measures to strengthen governance and management. This was the first step towards restoring confidence in the company, improving its financial position, and restoring its operational performance.

The new board members are Jabu Mabuza (chairman); Sifiso Dabengwa; Sindi Mabaso-Koyana; Mark Lamberti; Tshepo Mongalo; Malegapuru Makgoba; Busisiwe Mavuso; Nelisiwe Magubane; Rod Crompton; George Sebulela; Pulane Molokwane; Banothile Makhubela; and Jacky Molisane.

"Government has recommended the appointment of Phakamani Hadebe as the acting group chief executive with immediate effect. Further, the board is directed to appoint a permanent group chief executive and group chief financial officer within the next three months," the presidency said.

"The board is directed to immediately remove all Eskom executives who are facing allegations of serious corruption and other acts of impropriety, including Matshela Koko and Anoj Singh," it said.

Government called on all Eskom employees and other stakeholders who may have evidence of wrongdoing to bring this to the attention of law enforcement agencies so that culprits could be brought to book.

The ministers of public enterprises, energy, and finance would work together under Ramaphosa's leadership to deal with other structural issues, which included the funding model and other industry problems identified by the inter-ministerial committee on state-owned enterprises (SoEs) reform.

The parliamentary inquiry into alleged corruption at Eskom would resume on Tuesday, and Singh is expected to testify at 2pm. Koko is expected to testify on Wednesday.