South Africa launched a new line of bank notes on Saturday bearing the image of its first democratically elected president, Nelson Mandela, on the 22nd anniversary of his release from prison.

"It is my honour and pleasure to announce that new South African bank notes will bear the image of president Mandela, the first president of a free, democratic South Africa," President Jacob Zuma told a press conference in Pretoria.

The notes bear the former president's image circa 1990, the year he was freed from prison in a moment that came to symbolise the fall of apartheid and the rise of a new, democratic South Africa.

They replace a design featuring the "big five" safari animals -- Cape buffalo, elephant, leopard, lion and rhino -- introduced in 1992, two years before Mandela was elected the country's first black president.

All five notes -- 10, 20, 50, 100 and 200 rand ($1.29 - $25.80, 0.98 - 19.60 euros) -- will now bear Mandela's face on the front. Officials would not say what design would be on the back.

Central bank governor Gill Marcus said it was standard international practice for countries to upgrade their bank notes' security and design every six to eight years, and that South Africa had last enhanced security measures on its notes in 2005.

Marcus said Mandela, 93, had seen the notes and was "delighted".

The former president, whose public appearances have grown rare as he has become increasingly frail, was not present at the unveiling.

Zuma praised his legacy, calling him "Madiba," the clan name by which he is affectionately known.

"It needed a president like Madiba to lead a bruised nation like ours on a journey of forgiveness and reconciliation, and he acquitted himself exceptionally well, as he has always done in every aspect of his life."