In a statement on Thursday, the South African presidency said it wanted to "assure the nation and the world that the former president is in high spirits", suffering from an "ailment common to people of his age", adding that he had previously suffered tuberculosis and respiratory problems during his 1964-1982 incarceration.
Mandela, also known affectionately by his clan name 'Madiba', was the 1993 recipient of the Nobel Peace Prize for his struggle as an apartheid fighter and political prisoner. Local schoolchildren have hung messages of support outside the hospital, and US President Barack Obama said he wished the international icon a speedy recovery.