This emerged after the NPA revealed that it would not be prosecuting anyone for Zuma's alleged poisoning owing to the lack of evidence.
MaNtuli, as she is affectionately known, is the fourth woman Zuma married and the second current wife. She has three children with Zuma.
The former president is married to Sizakele Khumalo, Thobeka Madiba and Gloria Ngema, and engaged to Nonkan- yiso Conco. He and Nkosazana Dlamini Zuma, now minister in the Presidency, were divorced in 1998.
Another wife, Kate Zuma, is said to have committed suicide in 2000.
In 2015, MaNtuli was accused of being involved in a plot to poison the former statesman, and was subsequently banished from his Nkandla homestead.
Now she plans to sue the NPA and the Hawks for “malicious prosecution” after she was implicated in the poisoning saga, an allegation she vehemently denied.
MaNtuli wants to force the NPA and the Hawks to disclose what information they had against her to warrant being put up as a suspect.
On Monday, her lawyer Ulrich Roux said they would be sending a letter of demand to the NPA and the Hawks by the end of the week.
“We will file a letter of demand that will go out this week and they will have 30 days to respond to that.
“If they don't respond to the letter, we will issue summons in a court of law,” Roux said.
MaNtuli broke her silence at the weekend in an interview with news channel Newzroom Afrika about how difficult her life has been since being accused of plotting to kill her husband.
When the allegations against her surfaced, MaNtuli and her three children were banished from Zuma’s Nkandla homestead and moved to an apartment in Durban North.
“Yes, I’m happy to say I have been cleared and the world knows the truth, but the pain is still there,” she said.
In the interview, the former first lady said the allegations had turned her life into “a living hell”.
“I thought my husband knew me. It was a shock. I was subjected to machines (a lie-detector test). It has been five years of hell. We were moved to a one-bedroom guest house in Greytown to accommodate the children’s schooling.”
Zuma’s spokesperson, Vukile Mathabela, said the case was a family issue.
“I cannot comment on family issues; uBaba is going to court tomorrow and is busy in several meetings to prepare for that.”
Zuma is to appear in the Pietermaritzburg High Court today to appeal the ruling against his application for a permanent stay of prosecution of his arms deal corruption charges.
Roux said since being estranged from the former president, MaNtuli has not received financial support from Zuma or the state.
In the interview MaNtuli further said: “My kids and I would sleep together on a double bed in this tiny room and house. We were cramped.
“I asked to return to Nkandla but (former state security minister David) Mahlobo’s official said I’m no longer allowed there. I felt abused and betrayed all these years.”
She also said: “I resorted to legal help after lots of unsuccessful enquiries on the progress of the case. It took some weight off my shoulders to have a lawyer mediate things for me. I was tired.”
Yesterday, Roux said: “She doesn’t get spousal benefits. They were married in terms of customary law and accordingly have not been divorced But she doesn’t enjoy spousal benefits.” That’s one of the issues MaNtuli will sue for, he said.
In parliamentary questions this month Minister in the Presidency Jackson Mthembu said more than R59million had been spent on former presidents and their deputies since the start of the 2016/17 financial year.
Zuma, who resigned in February 2018, cost taxpayers just over R6.5million after FW de Klerk’s R5.6m bill.
Former president Kgalema Motlanthe, who was president for about eight months, had the largest bill at just under R17m.
Roux said Zuma had only seen their three children twice in three years. “He’s not even interested in the children. She will retain primary custody of the children. I don’t have any instructions to bring in any application for full guardianship from my client,” Roux said.
In June, Zuma and Sonono Khoza went to court to give her full powers over their 10-year-old child.
Zuma gave Khoza the right to remove the child from the country without his consent. He also agreed that if he or the child wanted to make contact with each other, the visitation rights would be facilitated by a professional.