Sources said the special meeting of the ZANU Central Committee, which was held in Harare, unanimously endorsed the votes of no confidence passed by the executives of the party’s 10 administrative provinces.
Saying an official announcement would follow shortly, the sources said Mugabe was replaced by Emmerson Mnangagwa, who until a fortnight ago was his deputy before he was sacked on 6 November.
First Lady Grace Mugabe was also expelled from the party, according to the sources.
Mugabe however remains technically Zimbabwe’s president and is expected to either resign voluntarily or face impeachment by parliament.
According to some officials, parliament is expected to meet on Tuesday to impeach the long-serving president.
The dramatic fall of the world’s oldest leader in a space of less than a week comes in the wake of a de facto military coup that saw him being placed under house arrest by the army.
The army accuses Mugabe of failing to run the country and trying to create a family dynasty by unconstitutionally appointing his wife his successor.
Mugabe has refused to stand down even as he has watched his support from party, security services and people evaporate in about six days.
His sacking comes a day after thousands of Zimbabweans marched in the streets of the capital Harare and other cities on Saturday in support of the army’s intervention.