Former South African President Nelson Mandela's health continues to be shrouded in mystery, with the presidency giving conflicting messages on where he was receiving treatment.

The presidency, which has taken over communications on Mandela's health, has declined to divulge any information on where the former president is hospitalised or comment on his condition.

"Mandela's health is improving," presidency spokesperson, Mac Maharaj said, urging the media not to speculate about the Nobel laureate's health.

"I would urge you that unless we provide an update or new information, you should proceed in the knowledge that Madiba's health is improving".

The 94-year old Mandela was flown to a Pretoria hospital from his home in Qunu, in the Eastern Cape, last weekend, for treatment of a recurring lung infection.

Madiba, as he is affectionately known, was initially reported to be at 1 Military Hospital, but this turned out to be untrue.

This weekend Mandela had an endoscopy to remove gallstones.

"The medical team decided to attend to a lung infection, as well as gallstones," Maharaj said.

Doctors described the operation as a success.

"The procedure was successful and Madiba is recovering," Maharaj said in a statement on Saturday.

"The medical team decided to attend to a lung infection before determining when to attend to the gallstones."

Tests done after Mandela was hospitalised on December 8 revealed a recurrence of a lung infection and that he had developed gallstones.

Journalists have camped outside a private hospital where they think Mandela is, while others set base at the apartheid icon's Houghton home.

On Sunday, President Jacob Zuma wished Mandela well while delivering his speech at the beginning of the ANC's 53rd elective conference in Mangaung in the country's Free State province.

Meanwhile, the South African National Editors Forum (Sanef) at the weekend expressed its disappointment in the government for deceiving the public over Mandela's hospitalisation.