However the prosecution is ready to proceed at the earliest date on which the court may be able to accommodate this case, should the defence so wish, the authority said in its first public statement on the case.
Zuma's lawyer Michael Hulley had said on Friday that the trial would begin on August 14. He was not immediately available for comment.
Hulley had earlier said that Zuma was being charged with racketeering, money laundering, fraud and corruption.
He said the charges were meant to smear Zuma's name, coming barely two weeks after Zuma's resounding victory to take charge of the ANC.
Prosecutors have previously charged Zuma with receiving bribes from the French arms firm Thint.
The case was dropped but prosecutors reopened their investigation of Zuma.
"We are obliged to carry out this mandate, however unpopular it might be"
Statement from National Prosecuting Authority
The charges against Zuma are likely to deepen political uncertainty in South Africa
There are increasing tensions between the ANC rank-and-file who back Zuma and the government headed by Mbeki who is seen by many Zuma supporters as instigating the legal action.
The NPA denied that the case was politically motivated.
"The NPA is sensitive to the controversy which this decision evokes. We are also aware of claims that the NPA is being misused to advance the political and other objectives of certain individuals. This is not so," the authority said.
"We are obliged to carry out this mandate, however unpopular it might be."
The prospect that Zuma could be embroiled in a lengthy trial that may overlap with the next general election in 2009 could heighten investor concerns about the country's stability.
Zuma has told the BBC that he would step down as ANC leader if he was found guilty in a trial.
Analysts said the ANC's National Executive Committee - its top decision-making body - may need to consider an interim leader when it holds its first meeting early in the New Year.
The ANC officials were not available for comment.