Eight of the 10 regional branches of Zimbabwean President Robert Mugabe's ruling ZANU-PF party called for him to resign today, state TV reported.

"The province resolved unanimously to recall the president... from being the president of the party and the government," said Cornelius Mupereri, a spokesman for the party's Midlands region.

He was one of several branch officials to appear on ZBC's nightly news to call for the 93-year-old leader to step down in what appeared to be a coordinated effort, with the officials reading almost identical statements.

Their declarations add to the already considerable pressure on Mr Mugabe to go, which has been mounting since generals seized power on Tuesday night and placed him under house arrest.

The army's intervention came after Mr Mugabe fired his vice president Emmerson Mnangagwa last week, who was thought to be the military's favoured candidate to replace Mr Mugabe if he died or resigned.

The sacking cleared the way for First Lady Grace Mugabe, who is 41 years younger than the president, to succeed him - a situation that is believed to have irked many senior military officers.

As well as the increasingly vocal opposition from within his own party, Mr Mugabe will face street protests tomorrow organised by veterans of the country's independence war and supported by long-standing opponents of the president.

Who are the key players in the Zimbabwe crisis?

Earlier today, Mr Mugabe attended a university graduation ceremony in the capital, Harare, in his first public appearance since the military seizure of power.

The United States, a longtime critic of Mr Mugabe over allegations of human rights abuses and election rigging, is seeking "a new era" for Zimbabwe, the US State Department's top official for Africa said, an implicit call for the nonagenarian leader to quit.

The unfolding drama in the capital, Harare, was thrown into confusion when a smiling Mr Mugabe was pictured shaking hands with Zimbabwe's military chief, the man behind the coup, raising questions about whether or not the end of an era was near.

Yesterday Mr Mugabe unexpectedly drove from his lavish "Blue Roof" compound, where he had been confined, to State House, where official media pictured him meeting military leader Constantino Chiwenga and South African mediators.

The official Herald newspaper carried no reports of the meeting's outcome, leaving Zimbabwe's 13 million people in the dark about the situation.

The army may want Mr Mugabe, who has ruled Zimbabwe since independence from Britain in 1980, to go quietly and allow a smooth and bloodless transition to Emmerson Mnangagwa, the vice president Mr Mugabe sacked last week, triggering the crisis.

The main goal of the generals is to prevent Mr Mugabe from handing power to his wife, Grace, who has built a following among the ruling party's youth wing and appeared on the cusp of power after Mr Mnangagwa was pushed out.