The United States has maintained a blockade on Cuba for nearly 40 years.  Its intent is to instigate the overthrow of the Castro regime so it can be replaced with a Capitalist one.

Mandela was highly critical of this US policy.  During his struggle against the racist minority government that controlled South Africa, Mandela recieved aid from the Cuban Government.

Mandela said, "Our moral authority dictates that we should not abandon those who helped us in the darkest hour in the history of the country."