Nelson Mandela, South Africa's first black president, was in critical condition Sunday, said Jacob Zuma, the country's current president.
Mandela, 94, has been hospitalized with a lung infection since early this month.
"The doctors are doing everything possible to get his condition to improve and are ensuring that Mandiba [Mandela's tribal nickname] is well-looked after and is comfortable. He is in good hands," Zuma said in a statement.
Mandela served 27 years in prison for his anti-apartheid activism and led South Africa as president following the fall of the system. The African National Congress, which was led by Mandela, issued a statement Sunday calling for the nation to keep the Mandela family in its thoughts.
"The African National Congress joins The Presidency in calling upon all of us to keep President Mandela, his family and his medical team in our thoughts and prayers during this trying time," said Jackson Mthembu, a spokesman for the party.