The Mugabes recently launched scathing attacks on Mnangagwa, accusing him of fanning factionalism within the ruling Zanu-PF party, said reports.
First to fire a salvo at Mnangagwa in front of thousands of party loyalists who gathered at Chipadze Stadium for the 8thPresidential Youth Interface rally was the first lady, who challenged the vice president to rein in his supporters. She accused him of insulting the presidency in his quest to succeed her husband.
Mnangagwa, who was present at the rally, did not say anything at the time, as he was not lined up to speak.
Both the first lady and Mnangagwa have publicly claimed that they are not harbouring any presidential ambitions.
President Mugabe followed his wife and told his supporters that Higher Education Minister Jonathan Moyo was part of a group of people who met in Tsholotsho in the early 2000s plotting that Mnangagwa takes over from him ahead of former vice president Joice Mujuru who now leads the opposition National People's Party.
"Jonathan Moyo was there in Tsholotsho when people were planning to install Mnangagwa as president. I really do not know what happened along the way that Moyo decided to abandon the project.
"We now hear that he is against Mnangagwa. If you ask Mnangagwa he will tell you that he was not there. Heis a qualified lawyer; he is clever and he knows how to defend himself," Mugabe was quoted as saying at the time.
The attacks on Mnangagwa have angered his allies, the war veterans, prompting them to hit back. They said an attack on the vice president as well as a recently ousted ex-war veterans minister Tshinga Dube was an attack on all war veterans, reportsNew Zimbabwe.
At a press conference in Harare, the Zimbabwe Liberation War Veterans Association Secretary General, Victor Matemadanda, said that they were also aware that a plan to disturb military structures was possibly on the cards "but they cannot disturb the history that we created".
Matemadanda also said that the Mugabes could not claim control of war veterans or the ruling Zanu-PF party, adding that the ex-freedom fighters "went to war out of their own volition".
He stated that war veterans persuaded the masses to join the struggle for independence, and did not go to war for the first family to enjoy the good life while most Zimbabweans were struggling.
Matemadanda reminded Mugabe that no one should claim owning the ruling party as it "belonged to everyone".
He said: "When President Mugabe says war veterans or freedom fighters who are still serving in the army have no role in Zanu-PF, I would not say he is lying; but that he has forgotten what we agreed that the gun shall free the people and guard the vote."