Nelson Mandela is breathing "without difficulty" after doctors drained fluid from his chest, the South African presidency says.
The 94-year-old former president was hospitalized in Pretoria with a recurrence of pneumonia.
South Africa's presidency announced Sunday that Mandela's condition continued to improve, reporting he "had a restful day and continues to receive treatment."
The government said in a statement it was "satisfied that the doctors are providing the former president with the best medical care possible to enable his recovery and comfort."
The infection resulted in a pleural effusion, a build-up of fluid on the lungs, which doctors have drained off, presidential spokesman Mac Maharaj said Saturday.
"This has resulted in him now being able to breathe without difficulty," Maharaj said.
"He continues to respond to treatment and is comfortable."
More from GlobalPost: Mandela making 'steady progress' in hospital
The statement gave the most detailed information yet on Mandela's medical condition, which until now was described simply as a lung infection.
University of Cape Town medical professor Keertan Dheda told Agence France-Presse that draining a pleural effusion was a "minor procedure," though "the older you are, the longer pneumonia takes to get better."
Mandela has been described as in good spirits and making steady progress. On Friday "he sat up and had his breakfast in bed," Maharaj told AFP.
Well-wishers in South Africa and around the world have been closely following the updates on Mandela's health since he was admitted to hospital on Wednesday night. As US President Barack Obama said: "We're all deeply concerned."
The South African presidency today thanked "all who have been praying for and sending messages of support to [Mandela] and his family."
At several Easter church services over the weekend President Zuma thanked thousands of South Africans who had prayed for Mandela.
“We also thank all people at home and around the world, who continue to keep Madiba and his family in their thoughts and to show their love and support in various ways," he said. "We also thank foreign governments for their messages of support."