Former South Africa President Thabo Mbeki tells Channel 4 News that President Zuma should "think about the country, the people".
Please wait while this video loads. If it doesn't load after a few seconds you may need to have Adobe Flash installed.
Mr Mbeki told Jon Snow in an interview that people were fed up with growing corruption in South Africa:
"I think there is a general mood in the country, across the country and across poltical divides. I think there's a sense among the people that there are some things that are not going right."
Referring to "what the Mandelas and others struggled for", Mr Mbeki said the when the people "look at certain things that are happening .. when they see this corruption in the country which seems to be increasing at all levels of government, people are aggrieved."
He added: "They are saying - but this is not what freedom was for."
At the memorial service to Mr Mandela, President Zuma was booed by the crowd, and this was widely blamed on dissatisfaction with his government and allegations of corruption.
On the question of whether Mr Zuma should consider stepping down, as he did, Mr Mbeki said:
"I would hope that if similar circumstances arose and confronted President Zuma, that he would think not about himself, but think about the country, the people. What is it that would be in the best interests of the people?
"I think that would be the honourable way to respond."