Former justice minister and anti-apartheid activist Penuell Maduna has hit back at former president Jacob Zuma, saying it is "a blatant lie" that he allegedly asked businessman Mzi Khumalo for money to entice the former president to retire from politics.

Zuma appeared before the State capture commission of inquiry on Monday and launched into a lengthy monologue in which he detailed how he had been "connecting the dots" since 1990.

The former president started the background to his evidence by claiming that there was a long-running conspiracy to have him removed.

At one stage, he told the commission how he learnt from Khumalo that Maduna and former National Director of Public Prosecutions Bulelani Ngcuka had approached the businessman, seeking money to fund a plan to force Zuma to leave politics

Earlier in his testimony, Zuma mentioned a figure of R20-million that he was allegedly offered to retire from politics and "go to Nkandla".

Speaking to News24 on Monday, Maduna said Zuma's claims were "a blatant lie".

"This is the first time this suggestion has come up. It is a blatant lie. I never asked Mzi [Khumalo] for a cent for anyone, not even for myself," he said.

He explained that he and Khumalo had shared a prison cell in Pietermaritzburg in the 1970s before Khumalo was moved to Robben Island.

"By the time Polokwane happened, I had left government, and there I had an opportunity to ask anyone, Cyril [Ramaphosa], Tokyo [Sexwale], Mzi, anyone for money. But I went to the banks.

"No, no, no. This is the first time this suggestion has been made. I am shocked, dumbfounded."

He was confident that Ngcuka and Khumalo would confirm this and suggested News24 contact both.

News24 has attempted to contact Ngcuka and Khumalo, but were unsuccessful.