Mandela was admitted to a hospital in Pretoria on 8 December for treatment of what was described as a lung infection.
Last week he also underwent a procedure to remove gallstones.
Amid speculation that Mandela may be allowed out to spend Christmas with his family, the Presidency confirmed on Monday that doctors have recommend that the iconic leader remain in hospital.
Presidential spokesman Mac Maharaj appealed to people to respect the privacy of Mandela and his family, especially on social media which have been passing out unconfirmed messages about the elder statesman's health in recent days.
"(Mandela) says that the knowledge of the love and support of his people is keeping him strong," Maharaj told media.
There have been several health scares around the 94 year old leader in recent years, prompting immense local and international interest in his health.
Government has however indicated that they would only issue statements if there was cause for alarm, citing the privacy rights of Mandela and his family.
