The 93-year-old dictator failed to publicly resign before the deadline of noon local time (10am GMT) today.
Zimbabwe’s ruling Zanu—PF will meet to start mapping out the impeachment of President Robert Mugabe on Monday, its chief whip Lovemore Matuke said.
Impeachment could see Mugabe kicked out by a vote in parliament in under a day if the process is fast tracked, constitutional experts say.
But there is a chance that Mugabe is bidding his time and could be on the brink of resigning in return for immunity.
Former British Foreign Secretary Sir Malcolm Rifkind has said that it is “quite possible” that Robert Mugabe will resign by the end of the day.
“I think it is quite possible that he will resign over the course of the day,” he told Sky News.
“Or he may wait a day or so to satisfy himself that the two-thirds majority in the Zimbabwean parliament will undoubtedly impeach him if he doesn’t go of his own choosing.”
Two senior government sources told Reuters that Mugabe agreed on Sunday to step aside but did not want to quit in front of the military.
“It would have looked extremely bad if he had resigned in front of those generals. It would have created a huge amount of mess,” one senior source within ZANU-PF said.
Another political source said the speech was meant to “sanitise” the military’s action, which has paved the way for Mnangagwa, a former security chief known as The Crocodile, to take over.
CNN said on Monday his resignation letter had been drawn up, with terms that included immunity for him and his hot-headed and unpopular 52-year-old wife Grace.