Struggle stalwart Ahmed Kathrada's official memorial service is expected to be held at the University of Johannesburg's Soweto Campus on Saturday morning, the Presidency said.

Deputy President Cyril Ramaphosa will deliver a message on behalf of government, according to a statement.

President Jacob Zuma extended his condolences to Kathrada's wife, former Public Enterprises Minister Barbara Hogan, and family. Kathrada died in hospital on Tuesday and was laid to rest at the Westpark cemetery, Johannesburg, on Wednesday.

The Presidency said Zuma extended his gratitude to all who had supported the family.

Former deputy president Kgalema Motlanthe, Gauteng Premier David Makhura, African National Congress (ANC) secretary general Gwede Mantashe, South African Communist Party general secretary Blade Nzimande, and the Congress of South African Trade Unions general secretary Bheki Ntshalintshali were some of the speakers at the funeral on Wednesday.

Zuma did not attend, in accordance with the Kathrada family's wishes.

Several speakers at the funeral criticised the current crop of ANC leaders. Motlanthe read excerpts from an open letter Kathrada wrote to Zuma in 2016, asking him to step down.