South Africans protest against Barack Obama's visit, just streets away from the hospital treating Nelson Mandela

South African protesters campaign against President Barack Obama’s three-nation tour of the continent (Reuters)

South African protesters campaigning against President Barack Obama’s three-nation tour of the continent gathered today just streets from the hospital where Nelson Mandela is critically ill.

The anti-apartheid hero and South Africa’s first black president has been fighting a severe lung infection in hospital for almost three weeks, where he will remain when President Obama arrives in Pretoria today.

His deteriorating condition – this is Mandela’s fourth and most serious hospitalisation in six months – has focused the world’s attention on South Africa and forced the White House to concede that the two leaders may not be able to meet this week.

Capitalising on the intense media focus, an estimated 200 trade unionists, student activists and South African Communist Party members gathered to protest against Obama's foreign policy, labelling it “arrogant, selfish and oppressive”.

“We had expectations of America's first black president. Knowing Africa's history, we expected more,” said Khomotso Makola, a 19-year-old law student. “He has come as a disappointment, I think Mandela too would be disappointed and feel let down.”

Obama’s critics in South Africa’s capital could be seen protesting with signs bemoaning the US’ use of drones in the War on Terror and the ongoing use of the Guantanamo Bay detention centre in Cuba.

During his weekend trip to Johannesburg, Cape Town, and Pretoria, the US President is scheduled to visit Robben Island, the former penal colony where Mandela was incarcerated for 18 of the 27 years he spent in prisons during the apartheid.