* Mandela spends sixth day in hospital on Tuesday
* Anti-apartheid hero, 94, suffering from pneumonia
Anti-apartheid hero Nelson Mandela's condition has not changed after a weekend improvement, the South African government said on Tuesday, and it denied media reports suggesting the former president had suffered a relapse in his pneumonia.
"His condition is unchanged as reported yesterday," presidency spokesman Mac Maharaj told Reuters. The government said on Monday there was "no significant change" in the condition of the 94-year-old Nobel Peace Prize laureate.
Asked about an NBC News report saying Mandela was still suffering a fluid build-up in his lungs, Maharaj said: "It is unfortunate that there are reports circulating in some media which suggest a deterioration, which is not true."
Mandela was admitted to hospital late on Wednesday for a recurrence of pneumonia. Doctors said on Saturday they had drained excess fluid from his lungs and he was breathing without difficulty.
It is the third health scare in four months for Mandela, who became South Africa's first black president in 1994. He was in hospital briefly in early March for a check-up and was hospitalised in December for nearly three weeks with a lung infection and after surgery to remove gallstones.
Mandela stepped down as president in 1999 and has not been politically active for about a decade. But he is still revered at home and abroad for leading the struggle against apartheid rule and then championing racial reconciliation while in office.
Global figures such as U.S. President Barack Obama have sent get-well messages.
Mandela has a history of lung problems dating back to when he contracted tuberculosis as a political prisoner. He spent 27 years in prison on Robben Island and in other jails for his attempts to overthrow the white-minority government.