Under the terms of the power-sharing agreement, Mugabe gets to name two vice-presidents from his Zanu-PF party. Party chairman John Nkomo is deemed a strong candidate to replace Msika.

As a member of Zimbabwe's Ndebele minority, which was brutalised by the army in a bloody crackdown on the opposition in the 1980s, Msika was one of the few senior Zanu-PF members to speak out about state-sanctioned human rights abuses.

He publicly took Mugabe to task over the killings of thousands of Ndebele civilians and later questioned the sincerity of Mugabe's apology.