Zimbabwe’s President Robert Mugabe says he will remain in office as long as he has the strength to do so.

The ninety year-old ruler was addressing a conference of his Zanu-PF party. He is Africa’s oldest head of state and is the only leader the country has known since gaining independence from Britain in 1980.

He sacked his vice-president, Joice Mujuru, earlier this week amid accusations that she was plotting against him, and he has caused further caused speculation about a successor by delaying in filling vacant senior posts.

Meanwhile his wife Grace, who is forty years younger than Mugabe, has been appointed leader of the influential Zanu-PF women’s league, leading analysts to speculate that she could be the one to succeed her husband.