Graca Machel, the wife of Nelson Mandela, yesterday described Zimbabwe's government as illegitimate and said regional leaders had allowed hundreds of thousands of people to die needlessly.
Zimbabwe is facing a humanitarian catastrophe as President Robert Mugabe and the opposition argue over a stalled power-sharing deal. Rights groups say scores of opposition activists have been murdered and tortured.
"Any government that goes out and assaults its people, its citizens, has lost completely any kind of legitimacy," Ms Machel said at a news conference, where Zimbabwean activists launched a hunger strike to pressure the Southern African Development Community regional body into taking a hard line with Mr Mugabe.
Asked if the veteran ruler should step down, Ms Machel said: "The people of Zimbabwe have already said so... the ballot has spoken." She has joined a growing list of prominent Africans who have criticised Mr Mugabe's authoritarian rule.