Mandela, also known by his clan name Madiba, was a "very human person" with a sense of humor who took interest in people around him, said F.W. de Klerk, South Africa's last apartheid-era president.
The two men negotiated the end of apartheid, finding common cause in often tense circumstances, and shared the Nobel Peace Prize in 1993.
In summarizing Mandela's legacy, de Klerk told eNCA television: "Never and never again should there be in South Africa the suppression of anyone by another."