Nelson Mandela 'continuing to improve' in Pretoria hospital

Nelson Mandela's health is continuing to improve (AFP)

Nelson Mandela's health is continuing to improve but the anti-apartheid hero remains in a serious condition, South Africa's president said today.

Jacob Zuma paid a visit to the 94-year-old in a Pretoria hospital, where the former president has been treated for six days, according to a statement released by the presidency.

"We continue to appeal to people to keep Madiba in their prayers and wish him a speedy recovery," Mr Zuma said, referring to Mr Mandela by his clan name.

Mr Mandela is being treated for a recurring lung infection, and it is his fourth spell in hospital since December.

Earlier in the day, Mr Zuma told members of parliament that Mr Mandela should be remembered not only for his years as the nation's first black president, but also for his time as a revolutionary.

Mr Zuma said South Africans should not create a "superficial" image of Mr Mandela, but remember his lifetime of work.

And the president also spoke of the need to improve the lives of the country's black majority, many of whom live in poverty nearly two decades after the end of racist white rule.

The leader of South Africa's anti-apartheid movement, Mr Mandela spent 27 years in prison during white racist rule. He was freed in 1990 and became South Africa's first black president in 1994.

His official Twitter feed noted that today was the 49th anniversary of his arrival at Robben Island, the prison off the coast of Cape Town where he spent the majority of his incarceration.