WATCH: George Bizos remembers Ahmed Kathrada

A tribute for struggle icon Ahmed Kathrada is underway at the Nelson Mandela Centre for Memory in Johannesburg. 

Kathrada died at the age of 87 at one of the city's hospitals this morning.

ALSO READ: Desmond Tutu bids farewell to Ahmed Kathrada

Advocate and human rights lawyer, George Bizos has been sharing some of his personal memories of his friend and comrade. 

Kathrada was among the defendants,  including former President Nelson Mandela, who were imprisoned after the Rivonia Trial. 

Her excellency, Zenani Mandela-Dlamini paid an emotional tribute to what she has referred to as one of her father's closest friends and confidants. 

"There are those people who come into your life and never leave because they are truly special. They have what we like to call presence - that rare ability to loom large in our lives. So that their impact on us is multiplied a thousand times over. Uncle Kathy belongs in this unique group. 

"Let me state my regard for him in this way so that it is clear just how highly me and my family regarded him. He was my other father. I have only the fondest memories of him. Ever gentle, always self-effacing but undoubtedly powerful," she said. 

Listen to the full bulletin below.