Mugabe has so far shown no signs of stepping down and has called for the weekly cabinet meeting to take place as usual on Tuesday.
Officials said the leader, who held power for almost four decades, was expected to resign, but Mugabe never formally stepped down.
He says the ruling party needs the backing of the MDC opposition group to have enough votes in Parliament but “they are supporting us”.
Zanu-PF’s action follows a weekend of high drama in Harare that culminated in reports Mugabe had agreed to stand down – only for him to dash the hopes of millions of his countrymen in a weird and rambling national address on Sunday night.
The statement comes after General Constantino Chiwenga said said the two had spoken and were moving to resolve the current crisis.
More details to follow.
According to NewsDay, a Zanu-PF MP who spoke on condition of anonymity said that they had been summoned for the caucus. Thousands of protesters demanded Saturday that Mugabe leave the presidency, which he has held since 1980.
Zanu PF Members of Parliament (MP) were on Monday locked in a meeting that started at 4pm as the party prepares to whip its legislators into line ahead of the vote of no confidence in President Robert Mugabe, which they plan to institute in the House of Assembly.
Mnangagwa fled the country shortly after his firing by Mugabe and his whereabouts are unknown.
Mugabe’s wife Grace, 52, secured prime position to succeed him, sidelining the vice president, Emmerson Mnangagwa, who was sacked.
A motion to impeach 93-year-old Mugabe will be tabled by Zimbabwe’s ruling Zanu-PF party on Tuesday, the party has confirmed.
By allowing cadres expelled in 2014 to come back, Zanu PF has also opened a window for former vice president Joice Mujuru and her cabal of more than 200 men and women who include Didymus Mutasa and Rugare Gumbo to troop back into the party.
Either Mugabe had not heard Zanu-PF’s announcement a few hours earlier that he had been removed as the party leader and replaced with Emmerson Mnangagwa‚ or he made a decision to override it.
Adding to its stunning reversal of allegiances, it threatens to impeach Mugabe if he does not resign by 12pm the next day.
“Arrogant Mugabe disregards ZANU-PF”, screamed the front page of the Daily News on Monday.
The ruling party also removed Grace from her position as Secretary of Women’s League “for promoting hate speech, divisiveness and assuming roles in powers not delegated to her office”.
The constitution says that in the event of a presidential resignation, he will be replaced by the vice president.
However, George Charamba, Mr Mugabe’s spokesman and possible drafter of the speech, told the Financial Times before the president went on air on Sunday that the generals were not seeking Mr Mugabe’s resignation. “We reiterate our call for an internationally-supervised process for the forthcoming elections, starting with the current voter registration exercise and ultimately the elections itself”.
“He is a disciplined cadre”, Mr. Mpofu said.