In a tweet, Zanu-PF said: “We regret all the embarrassment the old man has caused. Indeed after being president for so long R G Mugabe is struggling to accept reality. With or without his acceptance the process will proceed.”

The move to impeach the 37-year leader came after the “Grand Old Man” of African politics – once lauded across the continent as an anti-colonial hero – ignored a midday deadline imposed by the party, demanding he announce his resignation.

On paper, the impeachment process is long-winded, involving a joint sitting of the Senate and National Assembly, a nine-member committee of senators, then another joint sitting to confirm his dismissal with a two-thirds majority.

However, constitutional experts said Zanu-PF had the numbers and could push it through in as little as 24 hours.

“They can fast track it. It can be done in a matter of a day,” said John Makamure, executive director of the southern African Parliamentary Support Trust, an NGO that works with the parliament in Harare.

Zimbabwe’s parliament will convene on Tuesday.

Zanu-PF’s action follows a weekend of high drama that saw Mugabe and his wife Grace expelled from the party, and culminated in reports Mugabe had agreed to stand down – only for him to dash the hopes of millions of his countrymen in a bizarre and rambling national address on Sunday night.

Mugabe’s speech, in which he was flanked by military and called for national unity and farming reform, left many in the country of 16 million dumbstruck.

“I am baffled. It’s not just me, it’s the whole nation,” shocked opposition leader Morgan Tsvangirai said. “He’s playing a game.”

Former vice-president Emmerson Mnangagwa will step into the Zanu-PF leadership position.

Moments after Mugabe’s televised address, war veterans’ leader Chris Mutsvangwa, who has spearheaded an 18 month campaign to unseat Zimbabwe’s only leader, called for protests and a potential popular uprising if Mugabe refused to go.

“Your time is up,” he said at a press conference.

Since last week, Mugabe has been confined to his lavish “Blue Roof” residence in Harare under military house arrest. Grace and at least two senior members of her so-called G40 political faction are believed to be holed up in the same compound.

Jubilation and open condemnation of the long-time leader spilt out onto the streets of Harare on Saturday, with an estimated 1.6 million singing, dancing and taking selfies with soldiers in an event backed by the military.

The huge crowds gave a quasi-democratic veneer to the army’s intervention, backing its assertion that it was merely effecting a constitutional transfer of power, rather than an old-style coup, which would risk a diplomatic backlash.

At the University of Zimbabwe on Monday, students protested and refused to sit for exams, singing and demanding that Mugabe step down. The spokesman for the Zimbabwe National Students Union, Zivai Mhetu, said they want all universities shut down until he does.

Lawmakers from Zimbabwe’s main opposition party MDC will hold a meeting on Tuesday to decide whether to join their ruling party rivals to impeach 93-year-old President Robert Mugabe, the minority chief whip said.

Mugabe was once admired, even in the West, as the “Thinking Man’s Guerilla”, a world away from his image in his latter years as the stereotypical African dictator proudly declaring he held a “degree in violence”.

As the economy crumbled and opposition to his rule grew in the late 1990s, Mugabe tightened his grip around the southern African country, seizing white-owned farms, unleashing security forces to crush dissent and speaking of ruling until he was 100.

His fall from power is likely to send shock waves across Africa, where a number of entrenched strongmen from Uganda’s Yoweri Museveni to Democratic Republic of Congo’s Joseph Kabila are facing mounting pressure to step aside.

Reuters and Associated Press