Zuma, on his first state visit to Zimbabwe, said President Robert Mugabe, rival Prime Minister Morgan Tsvangirai and the leader of a small party in a coalition formed to try to end the crisis should fully implement their February unity agreement.
"The inclusive government has the responsibility to fully implement the global political agreement and thus create confidence in the process," he said.
He added that although some countries were offering Zimbabwe humanitarian assistance, they had set conditions for the provision of large-scale economic aid.
"Since these relate to the implementation of the global political agreement, to which the signatories remain fully committed, meeting these benchmarks should be a priority in the work of the inclusive government," he said.
Mugabe and Tsvangirai are feuding over the appointment of senior officials, sanctions and the pace of political reforms expected to end with democratic elections in two to three years.
Zuma began a two-day visit to Zimbabwe on Thursday aimed at keeping the power-sharing deal on track.
"The achievement of an effective recovery is also dependent on the removal of sanctions and other measures that hold up economic development," he said.
An economic recovery in once-prosperous Zimbabwe is important for South Africa. Millions of Zimbabweans have been driven to seek work in their much wealthier neighbour by a decade of economic decline and political crisis.
Zuma said outstanding disputes on the agreement brokered by his predecessor Thabo Mbeki could be resolved through mediation.
But his series of meetings on Thursday and Friday with Mugabe, Movement for Democratic Change (MDC) leader Tsvangirai and Arthur Mutambara, who heads a tiny MDC faction, could not immediately end their disputes.
"The important factor is that there is commitment amongst all parties which will make movement forward possible," said Zuma, current chairman of the 15-nation Southern African Development Community.
Mugabe’s and Tsvangirai’s parties are wrangling over the appointment of top officials including the central bank governor and attorney-general, over Western sanctions against Mugabe and over the pace of reform.
Zimbabwe says it needs $10 billion in foreign reconstruction aid, but has had little success in attracting it. Western countries want to see the government working effectively and implementing faster reform.
The government is under pressure from state employees, who earn an average $170 a month, threatening to strike for higher wages.
On Friday the Zimbabwe Teachers’ Association (ZIMTA), a union whose membership exceeds 43,000, said teachers would strike on Wednesday, when the new school term is due to begin. The stoppage could hit public examinations, due in two months.
ZIMTA is pressing for a wage increase to $500, from the current $165.
In what sounded like a tougher tone against Mugabe than adopted by Mbeki, Zuma said on Friday Africa must be united not just by geography but democratic values.
"For this reason, the promotion of democracy, the respect for human rights and the improvement of governance are vital for our success as a continent," he said. Reuters