Zimbabwe's former vice president Emmerson Mnangagwa, whose sacking last week triggered the military's takeover, has returned to the country, an aide said on Friday as ageing leader Robert Mugabe clung onto power.
Mnangagwa, who is a leading candidate to succeed to President Mugabe, flew back to Harare on Thursday after nearly a week abroad as army chiefs and the president met to negotiate Mugabe's exit from office.
The 93-year-old president has refused to resign, sources said, after soldiers this week put him under house arrest in a stunning turnaround for the veteran leader who has ruled Zimbabwe with an iron fist since 1980.
The generals took over late on Tuesday after Mnangagwa was sacked by the president and Mugabe's wife, Grace, emerged in prime position to succeed her increasingly frail husband.
The military was strongly opposed to Grace's rise, while Mnangagwa has maintained close ties to the defence establishment.
Mugabe's motorcade on Thursday took him from his private residence to the State House for the talks, which were also attended by envoys from the Southern African Development Community (SADC) regional bloc.
"He is refusing to step down. I think he is trying to buy time," said a source close to the army leadership who declined to be named.
Government TV showed Mugabe, the world's oldest head of state, dressed in a navy blue blazer and grey trousers standing alongside army chief General Constantino Chiwenga.
Zimbabwe was left stunned by this week's military intervention which came after Mugabe's advanced age sparked the bitter succession battle between Grace and Mnangagwa.
Mnangagwa, 75, was previously one of Mugabe's most loyal lieutenants, having worked alongside him for decades.
But he fled to South Africa following his dismissal and published a scathing rebuke of Mugabe's leadership and Grace's presidential ambitions.
The military said Friday they had detained some "criminals" in Mugabe's government in a reference to supporters of Grace's presidential ambitions.
Grace has not been seen since the military takeover.
State TV said a graduation ceremony at a university where Mugabe is the chancellor would proceed as planned on Friday, although it was unclear if he would attend.
'Very delicate time'
Morgan Tsvangirai, a former prime minister and long-time opponent of Mugabe, told journalists in Harare on Thursday that Mugabe must resign "in the interest of the people".
He added that "a transitional mechanism" would be needed to ensure stability.
Tendai Biti, who served as finance minister during the coalition government after the 2008 elections, called it "a very delicate time for Zimbabwe".
"A way has to be worked out to maintain stability," he said.
Harare's residents have largely ignored the few soldiers still on the streets with shops, businesses and offices operating as usual.
Eldred Masunungure, a lecturer at the University of Zimbabwe, said the formation of a "pre-election coalition" could be a viable response to the crisis.
The international community has been watching the crisis closely.
In Paris, the head of the African Union, Guinea's President Alpha Conde, warned that the continent "will never accept the military coup d'etat" in Zimbabwe and called for a return to the "constitutional order".
"(Problems) need to be resolved politically by the ZANU-PF party and not with an intervention by the army," added Conde.
Meeting in Botswana, the SADC called for an emergency regional summit to help resolve the crisis, urging Zimbabwe to "settle the political challenges through peaceful means".
Britain, Zimbabwe's former colonial ruler, called for elections scheduled for 2018 to go ahead.