The funeral of struggle veteran Ahmed Kathrada is expected to take place on Wednesday at the Westpark Cemetery in Randburg at 10am
Kathrada died in the early hours of Tuesday morning. He was 87.
He had undergone surgery relating to a blood clot on the brain earlier this month, but experienced several post-operative complications and contracted pneumonia in both lungs.
President Jacob Zuma announced a state funeral for Kathrada and ordered that all South African flags fly at half-mast until Wednesday.
Zuma said Deputy President Cyril Ramaphosa would lead the send-off of the much-loved stalwart.
Kathrada wrote an open letter to Zuma in 2016 asking him to resign.
Kathrada was arrested at the Lilliesleaf Farm in Rivonia in 1963.
On June 12, 1964 he and seven others, including Nelson Mandela, were sentenced to life in prison in the infamous Rivonia Trial.
Kathrada was released from a Johannesburg prison in 1989, after spending 26 years in prison.