Nelson Mandela’s granddaughter has accused Prince Harry and Meghan Markle of using her grandfather’s name to “make millions”.

Ndileka Mandela, 57, has spoken out about Harry and Meghan’s new US$100 million (NZ$158m) Netflix documentary, Live to Lead, which was released in late December claiming the couple are stealing his words.

The documentary which the Duke and Duchess of Sussex claim was “inspired” by the South African civil rights icon has “deeply upset”, Ndileka – head of the Thembekile Mandela Foundation – with her telling The Australian newspaper: “Harry needs to be authentic and stick to his own story, what relevance does grandad’s life have with his?”

In the trailer for the documentary, which focuses on inspirational public figures such as Ruth Bader Ginsburg and Greta Thunberg, Prince Harry is heard saying: “This was inspired by Nelson Mandela... who once said what counts in life is not the mere fact that we have lived.”

Meghan added: “It is what difference we have made to the lives of others that will determine the significance of the life we lead.”

Nelson Mandela's granddaughter has hit out at the Duke and Duchess of Sussex. Photo / AP

Ndileka told the news outlet she fears the couple are drawing a comparison between her grandfather’s release from prison and their decision to leave Britain when they stepped down as senior members of the royal family.

Angered by the comparison, she added: “Their marriage can never be compared to the celebration of grandad’s release... that’s chalk and cheese, there is no comparison.”

 “I admire Harry for having the confidence to break away from an institution as iconic as the Royal Family. Grandad rebelled against an arranged marriage to find his own path in life. But it comes at a price, you have to then fund your own life.

“I’ve made peace with people using granddad’s name but it’s still deeply upsetting and tedious every time it happens.”

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Ndileka went on to claim neither Harry nor Meghan ever really properly met Mandela.

She added: “I don’t believe he nor Meghan have ever properly met granddad, maybe when Harry was young at Buckingham Palace, but they are using his quotations in the documentary to draw in people and make millions without the Mandela family benefiting.

“I know the Nelson Mandela Foundation has supported the initiative but people have stolen grandfather’s quotes for years and have used his legacy because they know his name sells – Harry and Meghan are no different from them.”