Nelson Mandela is breathing without difficulty, South Africa's presidency has said, as he spends a third day in hospital with a lung infection.
Mr Mandela, 94, was comfortable and was continuing to respond to treatment, the statement said.
It said Mr Mandela had developed a pleural effusion - excess fluid in the lungs which had been drained to enable him to breathe more easily.
There are no details yet on how long he will remain in hospital.
After Mr Mandela was admitted to hospital late on Wednesday, President Jacob Zuma said people "must not panic".
The former president first contracted tuberculosis in the 1980s while detained on windswept Robben Island.
His lungs are said to have been damaged while working in a prison quarry. This latest spell in hospital is his fourth in just over two years.
Mr Mandela served as South Africa's first black president from 1994 to 1999 and is regarded by many as the father of the nation for leading the struggle against apartheid.
'Thoughts and prayers'
The statement read by presidential spokesman, Mac Maharaj, on Saturday said that Mr Mandela had been admitted to hospital "due to a recurrence of pneumonia".
It said: "Doctors advised that due to the lung infection, former President Mandela had developed a pleural effusion which was tapped. This has resulted in him now being able to breathe without difficulty.
"He continues to respond to treatment and is comfortable."
The statement said the presidency "would like to acknowledge and thank all who have been praying for, and sending messages of support for, Madiba and his family."
Madiba is Mandela's clan name and is widely used to refer to him.
On Friday, Mr Mandela's ex-wife, Winnie Madikizela-Mandela, told public broadcaster SABC that he was "doing well".
"He's responding very well to treatment," said Ms Madikizela-Mandela at a church service in Soweto.
The hospital Mr Mandela is attending has not been disclosed.
Last December Mr Mandela was treated for a lung infection and gallstones - his longest period in hospital since leaving prison in 1990. In February, he was treated for a stomach condition.
When asked whether people should prepare for the inevitable, Mr Zuma told BBC News: "In Zulu, when someone passes away who is very old, people say he or she has gone home. I think those are some of the things we should be thinking about."
But he stressed that Mr Mandela had been able to handle the situation "very well" so far.
BBC Africa correspondent Andrew Harding says South Africans have been praying for the recovery of Mr Mandela, who remains a moral beacon in the country despite withdrawing from public life almost a decade ago.
Despite his long imprisonment, Mr Mandela forgave his former enemies and as president urged South Africans of all races to work together and seek reconciliation.
In 1993 he was awarded the Nobel Peace Prize.
His main home is in Qunu, a small rural village in Eastern Cape province, where he says he spent the happiest days of his childhood.
However, doctors said in December he should remain at his home in the Johannesburg neighbourhood of Houghton to be close to medical facilities.