The office of president Jacob Zuma said in a statement that he had visited the 94-year-old former anti-apartheid leader in the evening and was informed by the medical team that Mr Mandela’s condition had become critical in the past 24 hours.
Mr Zuma also met Graca Machel, Mr Mandela’s wife, at the Pretoria hospital and discussed his condition, according to the statement.
He was accompanied on the visit by Cyril Ramaphosa, the deputy president of the country’s ruling party, the African
South Africa’s first black president, 94, was taken to hospital in Pretoria earlier this month for the third time this year, with a lung infection. “The doctors are doing everything possible to get his condition to improve and are ensuring that Madiba is well-looked after and is comfortable. He is in good hands,” said Mr Zuma, using Mr Mandela’s clan name, by which he is widely known in South Africa.
Mr Zuma appealed for prayers for Mr Mandela and his medical team.
Mr Zuma’s spokesman, said that the doctors’ use of the word “critical” was “sufficient explanation that should raise concern amongst us”.
“Therefore we want to assure the public that the doctors are working away to try and get his condition to improve,” he said. Wellwishers have been visiting the hospital in Pretoria for the past two weeks. The spokesman added that this was a stressful time for the Mandela family, and appealed for their privacy.
There has been little information about his condition in recent days. On 13 June, Mr Zuma said his health continued to improve but that his condition remained serious.
More recently, one of Mr Mandela’s grandsons, Ndaba Mandela, said his grandfather was getting better and he hoped he would be home soon.
Mr Mandela is seen by many around the world as a symbol of reconciliation, and Mr Zuma appealed to South Africans and the international community to pray for the ailing ex-president, his family and the medical team attending to him.
The ruling party expressed concern about the deterioration in Mr Mandela’s health.
“We welcome the work being done by the presidency to ensure that South Africans and people of the world are kept informed on the state of Madiba’s health,” the party said.
“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.”
Mr Mandela last made a public appearance at the final of the football World Cup in Johannesburg in July 2010. He has become increasingly frail in recent years.
On 29 April, state television broadcast footage of a visit by Mr Zuma and other leaders of the African National Congress to Mr Mandela’s home.
Mr Zuma said at the time that Mr Mandela was in good shape, but the footage – the first public images of Mr Mandela in nearly a year – showed him silent and unresponsive, even when Mr Zuma tried to hold his hand.
Mr Mandela’s history of lung problems dates back to his time at Robben Island prison near Cape Town. The Nobel Peace Prize winner is believed to have suffered damage to them while working in a prison quarry.
He was released in 1990 after 27 years and went on to serve as president from 1994 to 1999.