Zapiro's latest cartoon may have gone too far, but so has the behaviour of some of South Africa's leaders, the Christian Democratic Party (CDP) said on Tuesday.
"The CDP would say that Zapiro has gone too far. Shockingly so," said CDP leader Theunis Botha in a statement.
"Yet, on the other hand, we have a president and many others holding public office, whose morals are, to say the least, questionable and whose influence is causing the nation to draw further away from what is morally and ethically acceptable."
The cartoon by Jonathan Shapiro depicts an erect penis with a showerhead and legs standing before a mirror with an accompanying limerick about Zuma.
Headed "The Spear to be raised at Social Cohesion Summit", the cartoon was published in the Mail & Guardian on Friday.
The CDP believed leaders should be respected but in turn, they should display the utmost integrity.
"On the other hand those involved in journalism, such as Zapiro, should fearlessly defend the truth and in the public interest expose those leaders who are corrupt and who negatively affect the moral standards of the nation by setting a bad example."
Botha said it was not possible to take sides in this matter.
"How can we even consider taking sides, when the decadent state of our nation has brought this terrible situation upon us?
"The very people who should be putting their house in order are now telling another to put his house in order.
"Apologies are threateningly being demanded of Zapiro. Yet our leaders cover up their actions and refuse to apologise."
Botha called on all parties, particularly those in leadership, to put their houses in order.