Update 5.45pm: Zimbabwe's incoming leader has said his country is a "new and unfolding democracy" as he returned from a brief exile.
Emmerson Mnangagwa thanked the people "in the name of Our Lord" in his first public speech since President Robert Mugabe announced his resignation.
He addressed a huge crowd outside ruling party headquarters and described what he said were recent attempts to kill him.
Mr Mnangagwa said the pressure to "derail the process" of getting Mr Mugabe to step down was intense but "the will of the people will always, always succeed".
The new leader spoke hours after returning to the country.
He fled earlier this month after his firing by Mr Mugabe who then installed his wife Grace as his preferred successor.
Mr Mnangagwa was introduced as "president-in-waiting" by a speaker who praised Zimbabwe's military as "the most disciplined army in the world" during the past week's events.
He will be sworn in on Friday following Mr Mugabe's stunning resignation after 37 years at the helm.
Chief whip Lovemore Matuke confirmed Mr Mnangagwa was meeting Politburo members at party headquarters for a briefing "on what has been happening in his absence".
Update 5.05pm: Hundreds of people have gathered in expectation of a speech by Zimbabwe's incoming leader Emmerson Mnangagwa after his return to the country.
The crowd gathered outside the ruling party headquarters where Mr Mnangagwa is being briefed.
He will be sworn in on Friday following Robert Mugabe's stunning resignation after 37 years.
Chief whip Lovemore Matuke confirmed that Mr Mnangagwa is in the capital, Harare, and will meet Politburo members at party headquarters for a briefing "on what has been happening in his absence."
Mr Mnangagwa fled the country after former president Robert Mugabe fired him earlier this month, leading the military to step in.
Mr Mugabe resigned yesterday amid impeachment proceedings after an outpouring of opposition to his 37-year-rule.
Update 2.12pm: Zimbabwe's fired vice president was set to return to be sworn in as the new leader, after Robert Mugabe announced his stunning resignation during impeachment proceedings against him.
The state-run broadcaster said Emmerson Mnangagwa would arrive at Manyame Air Base in the capital, Harare, at 6pm.
The Parliament speaker said he would be sworn in on Friday after the ruling party notified him of its nomination of Mr Mnangagwa to replace Mr Mugabe until the end of the term next year.
Several hundred people gathered singing and cheering outside the base in anticipation of Mr Mnangagwa's arrival.
A man in the crowd, Godwin Nyarugwa, who has several university degrees but no job, said Zimbabwe has been through "crisis after crisis" and Mr Mnangagwa seems best suited to lead the country forward.
"We have to try him and see," he said. "If he doesn't come up with something, we need to change him as well."
Zimbabweans cheered and danced in the streets of Harare late into the night after the resignation, thrilled to be rid of a leader whose early promise after the end of white minority rule in 1980 was overtaken by economic collapse, government dysfunction and human rights violations.
Now the focus turns to Mr Mnangagwa, Mr Mugabe's long-time deputy who was pushed aside earlier this month as unpopular first lady Grace Mugabe positioned herself to replace him and succeed her husband.
It was reported that Mr Mnangagwa would be met on arrival by army commander Constantino Chiwenga and ruling party officials and was expected "to meet Mugabe for a briefing."
"Everyone was engulfed with excitement and they are looking for a better future, a brighter future with work," said Patrick Musira on the streets of the capital.
Update 10.18am: Zimbabwe’s recently fired vice president is set to return to be sworn in as the country’s new leader after Robert Mugabe announced his resignation in the middle of impeachment proceedings against him.
It is thought that the new president will be sworn in on Friday.
Zimbabweans erupted in response yesterday, cheering and dancing in the streets late into the night, thrilled to be rid of a leader whose early promise after the end of white minority rule in 1980 was overtaken by economic collapse, government dysfunction and human rights violations.
Now the focus turns to Emmerson Mnangagwa, Mugabe’s long-time deputy who was pushed aside earlier this month as unpopular first lady Grace Mugabe positioned herself to replace him and succeed her husband.
Mr Mnangagwa fled the country, claiming to have received threats on his life.
That led the military to step in a week ago, opening the door for the ruling party and the people to publicly turn against the president.
It is not clear what 93-year-old Mugabe and his wife will do next. Mugabe, who was the world’s oldest head of state, said in his resignation letter that legal procedures should be followed to install a new president "no later than tomorrow".
The speaker of parliament is expected to speak to reporters on the way forward.
Zimbabweans woke up to the first day in 37 years without Mugabe in power. With some nursing hangovers, they looked over newspaper headlines such as "Adios Bob and Ta-ta President".
"I think this change of government is like a new breath of fresh air right across the country," said Patrick Musira on the streets of the capital, Harare. "Everyone was engulfed with excitement and they are looking for a better future, a brighter future with work."
Zimbabwe’s new leaders are faced with a once-prosperous nation whose economy has collapsed, sending well-educated but frustrated young people into desperate work as street vendors, while many have left the country.
Mr Mnangagwa is a former justice and defence minister who served for decades as Mugabe’s enforcer, a role that earned him the nickname "Crocodile".
Many opposition supporters believe he was instrumental in the army killings of thousands of people when Mugabe moved against a political rival in the 1980s.
So far in the current political turmoil, Mr Mnangagwa has used inclusive language, saying in a statement hours before Mugabe’s resignation that all Zimbabweans should work together to advance their nation.
"Never should the nation be held at ransom by one person ever again, whose desire is to die in office at whatever cost to the nation," Mr Mnangagwa said.