Former South African President Nelson Mandela continues to get better in a Pretoria hospital, current President Jacob Zuma has said. He added that the revered ex-leader remained in a serious condition as he recovered from a lung infection. "Over the last two days, although he remains serious, his doctors have stated that his improvement has been sustained," Mr Zuma said. He added that Mr Mandela "continues to engage with family". Mr Zuma made his remarks while addressing a gathering for Youth Day in KwaZulu-Natal province in remembrance of the 1976 Soweto uprisings against apartheid. He asked the audience to join him in wishing Mr Mandela a happy Father's Day. The BBC's Mike Wooldridge in Johannesburg says that Mr Mandela's grandson Mandla spoke in a similar vein on Saturday, talking of good progress - but no-one has yet indicated when he might leave hospital. While they might hold out hope, our correspondent adds, many South Africans clearly recognise his continuing vulnerability. Mr Mandela became South Africa's first black president in 1994 after leading the struggle against apartheid. He stepped down five years later. Global icon He has been in intensive care since he was taken to hospital on 8 June for the third time this year. Each visit has provoked greater concern in South Africa and around the world over the welfare of the global icon, who will be 95 next month. Mr Mandela's wife Graca Machel has been at his bedside regularly since calling off a trip to London last week. In December, Mr Mandela spent 18 days undergoing treatment for a lung infection and gallstones. Before his latest admission to hospital, he had been ill for some days, with a recurrence of his long-standing lung problems. Mr Mandela was imprisoned for 27 years for his role in the fight against apartheid and is believed to have suffered damage to his lungs while working in a prison quarry. He contracted tuberculosis in the 1980s while being held in jail on the windswept Robben Island. He retired from public life in 2004 and has rarely been seen at official events since.