Former President Nelson Mandela is expected to spend a sixth day in hospital on Thursday for a recurring lung infection.
President Jacob Zuma told MPs on Wednesday that Mandela was responding well to treatment.
"I am happy to report that Madiba is responding better to treatment from this morning," he said while opening debate in the National Assembly on the presidency's budget vote.
Zuma said the government was "very happy with the progress that he is now making, following a difficult last few days".
Mandela, 94, was admitted to a Pretoria hospital in the early hours of Saturday morning in a "serious, but stable" condition. His condition has remained unchanged since then.
Mandla Mandela, the ailing icon's grandson, said on Wednesday that the family appreciated the support it had received from South Africans and the global community.
"We want to say thank you, and we appreciate all your support that you show towards our grandfather and your father," he told journalists outside Mandela's Houghton home in Johannesburg.
Mandela's ex-wife, ANC MP Winnie Madikizela-Mandela arrived at the hospital just after 3pm on Wednesday. Moments later, Mandela's daughter Makaziwe arrived.
Earlier in the day, Mandla, another grandson, Ndaba, Mandela's wife Graca Machel, and his daughter Zenani, were at the hospital.