President Jacob Zuma believes it is not up to him to ensure that criminal charges against African National Congress (ANC) MP Brian Molefe are pursued.

And the new MP’s presence in Parliament did not diminish the institution's dignity in any way, Zuma told MPs during a question and answer session in the National Assembly on Thursday.

The president was answering questions on the possibility that the former Eskom CEO could join the executive.

"The appointment of persons to the executive is the prerogative of the president of the republic as outlined in the Constitution. The president communicates publicly if he takes such a decision," he said.

Zuma said Molefe, who was mentioned in former Public Protector Thuli Madonsela's State of Capture report as having had contact with the Gupta family, had not been found guilty of any crime.

Molefe announced his resignation from Eskom a few days after the report was released. He was sworn in as an ANC MP on February 23.

"If there are allegations, they are not convictions. Allegations are allegations," Zuma said.

He said he did not understand calls in the House for someone to be convicted and punished based on allegations.

Zuma said he could not speak for Molefe on how he had been treated before the state capture report was made public in November last year. He said Madonsela had treated him (Zuma) unfairly.

He had not been given a chance to go through Madonsela’s questions before they were sprung on him, he claimed.

"I don’t know how it [the process] treated Mr Molefe, but I know the report was unfair, the way it was handled," he said.