“We are happy that he is not in any danger and thank the doctors for their hard work and professionalism. He is receiving good medical care and is expected to be discharged from hospital either tomorrow or Monday,” Zuma said in a statement.

“Madiba is fine and fully conscious and the doctors are satisfied with his condition, which they say is consistent with his age,” Zuma said, referring to Mandela by his affectionate clan name.

“He was in good health before admission in hospital but doctors felt the complaint needed a thorough investigation. He underwent a diagnostic procedure as part of his ongoing medical management.” Zuma’s office said earlier that Mandela has been admitted to hospital for a long-standing abdominal complaint, but relatives and officials have rushed to reassure the nation that his overall health is good.

In 2011, he spent a few days in a private Johannesburg hospital with an acute respiratory infection.

Mac Maharaj, Zuma’s spokesman, said he could not immediately elaborate but that he would be issuing regular updates. The South African military, which had taken charge of Mandela’s health care after he was hospitalized last year, and a spokesman for Mandela’s office said they would have no statement Saturday.

Keith Khoza, spokesman for Mandela’s African National Congress, said Zuma’s office had reassured members of the nation’s governing party.

Mandela “just had abdominal pains for some time now and the doctors decided a while ago that perhaps they should admit him, with a view to check those abdominal pains, so it wasn’t an emergency admission,” Khoza told reporters. “He’s fine, he’s in good health.”

Mandela became South Africa’s first black president in 1994 after spending 27 years in prison for his fight against racist apartheid rule, and he was awarded a Nobel Peace Prize for his efforts.

Well-wishers like Derek Kemper, a 47-year-old emergency services consultant, said they hoped Mandela would soon recover.