Mugabe to resign after 37 years: sources

Robert Mugabe has been told to quit or face impeachment amid Zimbabwe's de facto coup

Zimbabwe's President Robert Mugabe is resigning after nearly four decades in power, according to an official close to the talks on his departure.

The news comes hours after the ruling party's Central Committee fired Mugabe as party leader on Sunday and said if he didn't resign as the country's president by noon Monday it would start impeachment proceedings.

Mugabe is expected to address the nation on state-run television.

The official close to the talks spoke on condition of anonymity because he was not authorised to speak to reporters.

It is an extraordinary end to 37 years in power for the world's oldest head of state, who had vowed to rule until death.

The 93-year-old has been under house arrest since the military moved in Tuesday, angered by his firing of his longtime deputy and the positioning of unpopular first lady Grace Mugabe to succeed him.

Mugabe tried to buy time in negotiations with the military on a dignified exit but quickly found himself isolated.

Tens of thousands of people poured into the streets of the capital on Saturday to demand that Mugabe, one of Africa's last remaining liberation leaders, step aside after overseeing the once-prosperous country's economic collapse.

The deputy Mugabe fired, former Vice President Emmerson Mnangagwa, is poised to be Zimbabwe's next leader after the Central Committee made him its nominee to take over when Mugabe goes.