President Jacob Zuma's children are "content" to share their father with "twenty or more" siblings, his son Duduzane said.

"We as a family are content with the polygamous nature of our household," he said in a statement.

"We are content to have twenty siblings or more."

Duduzane said his father had his children's blessing to add to the brood if he so wished.

"It is my father's right within the context of his culture to have as many children as he wishes."

He said as a "citizen" his father had a right to "practice his culture.

"As a citizen of South Africa, my father has the same right to privacy and to practice his culture as any other citizen."

He said many of the Zuma children were adults who could help raise the younger ones.

"Many of us are adults who are quite capable of taking care of ourselves and our minor brothers and sisters."

Duduzane said his father's care for children extended beyond his biological brood.

"He is a father who has never denied any of his children and cares for the welfare of his family and for that of millions of other children in South Africa."

The family was proud of their father.

"We love our father and are very proud of the loving, fair, just, principled and dignified manner in which he heads up our family."

Duduzane wanted to show the world the president's children were "real people".

"I have decided to make this statement to demonstrate to the world that Mr Jacob Zuma's children are real people with feelings, emotions and personalities and not just faceless statistics."

This week the president, who has three wives and a fiancee, confirmed he had a relationship with Sonono Khoza, daughter of World Cup local organising committee chairman Irvin Khoza, and they had a daughter together last year.

"I said during World Aids Day that we must all take personal responsibility for our actions. I have done so," a statement issued on Zuma's behalf on Thursday read.

"I have done the necessary cultural imperatives in a situation of this nature, for example the formal acknowledgement of paternity and responsibility, including the payment of inhlawulo to the family."

The gist of the criticism levelled at him was that his actions were not in line with the government's HIV/Aids policies -- a suggestion he disagreed with.

On Thursday, the president's spokesman Zizi Kodwa announced Zuma had cancelled his public engagements for the next two days so hecould rest following a "hectic" schedule.

Kodwa told Sapa: "The president is fine. It's just his hectic schedule."

On Thursday Democratic Alliance leader Helen Zille dismissed Zuma's attempts to place his love child in the context of Zulu culture, saying it was no excuse for infidelity.

"No culture, polygamous or otherwise, justifies cheating on your wives," she wrote in her weekly newsletter SA.