Johannesburg - Deposed nonagenarian Robert Mugabe, 94, on Sunday said he can not vote for those "who have tormented me".
It was the first time that Mugabe has spoken about his choice on the candidates - Zanu PF's Emmerson Mnangagwa, 75, and 40-year-old Nelson Chamisa of the MDC Alliance.
Mugabe said he has not met Chamisa and has never worked with him. He said he wished whoever wins well.
The former president, however, said Chamisa "seems to be doing well".
Mugabe, who was removed after the intervention of the army in November, said: "We must have constitutionality".