The 94-year-old spent the day at the One Military Hospital in Pretoria, after getting a “good night’s rest,” but faced a new set of undisclosed checks and the prospect of a third night in admission.
“The doctors will still conduct further tests today. He is in good hands,” the presidency said in a statement.
The defence ministry, which is responsible for the former president’s health care, told AFP there is “no immediate danger to him at this stage,” but offered few details about his condition.
Mandela – who received the Nobel Peace Prize 10 years ago today – was flown to the country’s leading military hospital from his rural homestead on Saturday.
Defence Minister Nosiviwe Mapisa-Nqakula visited Mandela early on Monday and said the revered statesman was “doing very, very well”.
“He is comfortable, he continues to receive treatment which… (is) routine and that should be expected of a person of his senior age.”
Officials have kept silent about the procedures involved and have not given any specifics of his medical condition.
It was unclear if Mandela would spend a third night in hospital.
“That (decision) is still in the hands of the doctors… They are saying they are doing further tests,” presidential spokesman Mac Maharaj told AFP.
But it is not the first health scare for the nonagenarian, who in February spent one night in hospital for a minor procedure to probe persistent abdominal pain.
In January 2011, Mandela had the country on edge when he was admitted for two nights for an acute respiratory infection. He was discharged in a stable condition for home-based care and intense medical monitoring.
Madiba, as he is affectionately known by South Africans, retains a prominent place in the national psyche, despite leaving office more than a decade ago – a virtual lifetime in the quick-moving politics of this born-again nation.
South Africans united to offer prayers for their ailing national hero, who was the country’s first black president.