A statement from the South African government said Nelson was still in critical condition but was showing sustained improvement after being hospitalized June 8 with a recurring lung infection.
Zuma urged people to pray for Mandela -- also known as Madiba -- and to continue to do good works in his name, the BBC reported Tuesday. Zuma said the best way for people to honor the former leader would be to contribute to the children's fund's goal of building a 238-bed academic and pediatric hospital.
"Madiba loves children and wants the best for them. He wants us to ensure that they have a better future," Zuma said. "The hospital will be one of the most inspiring legacies of this remarkable statesman and leader of our people, and we humbly invite all sectors to actively support this project."
Mandela, who was incarcerated for 27 years during the fight to end South Africa's apartheid system before coming the country's first black president in 1994.