Anti-apartheid icon Nelson Mandela who has been hospitalized for more than a week, "continues to get better", South African President Jacob Zuma said on Sunday.

"Over the last two days, although he remains serious, his doctors have stated that his improvement has been sustained," Zuma said at a rally to commemorate the country's National Youth Day in Newcastle, KwaZulu-Natal Province.

"He (Mandela) continues to engage with family," Zuma said.

"Let me at this juncture, invite you all to keep Madiba (Mandela's nickname) in our thoughts and prayers. As you are aware, (former) President Nelson Mandela is still in hospital in Pretoria, " said Zuma.

"I invite you to join me today, in wishing Madiba a very happy Father's Day today," Zuma said. "We love him and know that he loves us too."

Mandela, who turns 95 next month, was rushed to hospital on June 8 after days of experiencing a deterioration in his recurring lung problem which was the result of tuberculosis developed when he was in prison under the apartheid rule.

On Thursday, Zuma visited Mandela and said his condition "continues to improve but his condition remains serious."

Mandela has been in and out of hospital several times since last December, raising concern about his health.