Mugabe and Tsvangirai have been feuding over the appointment of senior officials, sanctions and the pace of political reforms in the country.
Zuma ended his two-day trip to Zimbabwe on Friday in a visit aimed at keeping the power-sharing deal between the two men on track.
Haru Mutasa, Al Jazeera's correspondent in Harare, said: "Zimbabweans were hoping for some answers to a way out of the problem the country is in, they didn't really get any.
"There were no solutions yet to the sticking points that were dragging on this inclusive government.
"All he [Zuma] said was that all the parties involved are committed to working out the differences and he said that he would take the Zimbabwe issues to the Southern African Development Community (SADC) summit which will be held next month in the Democratic Republic of Congo."
In what sounded like a tougher tone against Mugabe than adopted by Thabo Mbeki, his predecessor, Zuma said on Friday that 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.
He said that although some countries were offering Zimbabwe humanitarian assistance, they had set conditions for the provision of large-scale economic aid.
"The achievement of an effective recovery is also dependent on the removal of sanctions and other measures that hold up economic development."
The president held a series of meetings on Thursday and Friday with Mugabe, Tsvangirai, the leader of the Movement for Democratic Change (MDC) and Arthur Mutambara, who heads a small MDC faction.
|Zuma held talk with Morgan Tsvangirai, pictured, the MDC leader [AFP]
"The important factor is that there is commitment amongst all parties which will make movement forward possible," said Zuma, the current chairman of the 15-nation SADC.
After dining with Zuma on Thursday, Mugabe sought to downplay his differences with Tsvangirai, calling their disputes "teething problems".
"I am happy to inform you that the inclusive government is alive and well," Mugabe told Zuma.
"Indeed, a political accommodation of this nature is bound to experience teething problems."
Zimbabwe says it needs $10bn in foreign reconstruction aid, but has had little success in attracting it with Western countries wanting to see the government working effectively and implementing faster reform.
The government is also under pressure from state employees, who earn an average of $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, with Zimta pressing for a wage increase to $500 from the current $165.
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.