Kweku Mandela, 26, said the $20m (£13m), six-part series would focus on “Mandela the man” rather than “Mandela the saint”, looking candidly at what he had achieved and which of his dreams were still to be realised.
Spanning six decades, it will examine his family life, his 27 years in prison and his negotiations with the apartheid government that led to his election as the country’s first black president in 1994.
Mr Mandela said his grandfather, 93, had given his approval to the series, which will be entitled “Madiba” after his Xhosa clan name, on certain conditions.
“He understands that there is a general interest in him and is happy for these stories to be told but he wants them to be told accurately,” he said.
“Something which is also a major thing for me is that he wants it to be reiterated that he didn’t do this alone, that people like Walter Sisulu, Oliver Tambo and Joe Slovo should get the credit they deserve.”