The comments are likely to reflect President Robert Mugabe’s anger with Zuma, who condemned events in Zimbabwe in unusually strong language at a regional summit last week.
“President Jacob Zuma’s erratic behaviour is the stuff of legends,” the Sunday Mail said in an editorial.
“The problem with Mr Zuma now is that his disconcerting behaviour has become a huge liability, not only to South Africa but also to the rest of the continent.”
Along with the leaders of Zambia and Mozambique, Zuma demanded an end to a crackdown on Movement for Democratic Change (MDC) activists.
International pressure forced Mugabe’s ZANU-PF party into a unity government with Prime Minister Morgan Tsvangirai’s MDC two years ago to try to ease an economic crisis.
The alliance is a strained one and ZANU-PF continues to control the security forces. In recent weeks, these have cancelled MDC rallies and detained MDC figures, heightening tension before a possible general election this year.
The Sunday Mail is Zimbabwe’s main government mouthpiece and is unlikely to have published such comments, the strongest yet against Zuma, without official sanction.
The paper accused Zuma, head of the African National Congress (ANC) party and the Southern African Development Community’s main negotiator on Zimbabwe, of being a dishonest broker. It said he had betrayed Africa by voting for a no-fly zone over Libya at the United Nations Security Council.
“Mr Zuma’s duplicity is astounding. With such leaders, Africa is in mortal danger,” the paper said.
“The same President Zuma who voted for the bombardment of Libya is now speaking out against the use of military force by the United States, Britain, France and their allies,” it went on. “Does South Africa have a foreign policy at all or has the ANC entered the era of Mickey Mouse posturing?”
Zuma’s office hit back, saying in a statement that South Africa’s position on Libya was “clear and unambiguous” in rejecting any attempt at regime change or foreign occupation of Libya.
It added that relations with Zimbabwe remained “warm and cordial”.
Jonathan Moyo, a member of Mugabe’s ZANU-PF Politburo, wrote in the Sunday Mail: “President Zuma is now tainted beyond recovery by the Libyan situation and his commitment to the African cause has become questionable.”