Former South African president Nelson Mandela is suffering from a recurring lung infection, but is responding to treatment in hospital in Pretoria, according to officials.
A statement from presidential spokesman he is "receiving appropriate treatment and he is responding to the treatment."
Mandela was admitted to hospital on Saturday. Africa Correspondent Rohit Kachroo reports:
Last January, the 94-year-old was admitted to a Johannesburg hospital for what officials initially described as tests but what turned out to be an acute respiratory infection.
Mandela has a history of lung problems and health problems. He contracted tuberculosis during his years in prison and had surgery for an enlarged prostate gland in 1985. In 2001, he underwent radiation therapy for prostate cancer.
Mandela is revered across the world for being a leader of the struggle against apartheid in South Africa and for preaching reconciliation once he emerged from prison in 1990 after 27 years.
He won South Africa's first truly democratic elections in 1994, and served one five-year term.
The Nobel laureate has retired from public life in recent years to live in his remote village of Qunu, in the Eastern Cape, and last made a public appearance when his country hosted the 2010 World Cup soccer tournament.
He has grown increasingly frail in the past few years.