Although a friendship already existed between Castro and Mandela, formal diplomatic relations between Cuba and South Africa did not begin until after May 11, 1994.
For Mandela's 90th birthday, Castro sent the leader a glorifying message:
“Glory to you, Nelson, who while in prison for 25 years defended human dignity! Slander and hatred could do nothing against your endurance of steel. You were able to resist and, without knowing or looking for it, you became a symbol of what is most noble in humanity. You will live in the memory of future generations, and in your memory the Cubans who died defending the liberty of their brothers in other lands of the world."