The dictator failed to meet the 12.00pm local time, 10.00am (GMT) deadline for his resignation set by the country’s generals following last week’s coup.
Former deputy leader Emmerson Mnangagwa said: “The main charge is that he has allowed his wife to usurp constitutional power when she has no right to run the government.”
The 93-year-old’s own party, Zanu PF, have ditched him as leader ordering him to stand down and have now started moves to impeach him.
Mugabe recently fired Mnangagwa to pave the way for Grace to seize power by succeeding him.
Led by Mnangagwa, MPs began work on a plan to remove him as president ending his brutal reign.
These plans could see the despot out of office before the end of the week, with a motion due to be presented to the Zimbabwe parliament later today.
Speaking to the BBC, Mnangagwa said: ”We are expecting the motion to be moved tomorrow… and hopefully by Wednesday - because the charges are so clear - we expect that by Wednesday, we should be able to vote in parliament."
Serious misconduct, violation or failure to uphold the constitution or incapacity are all legal grounds for impeachment in the country.
Speaking of Mugabe’s wife, Grace, Mnangagwa said: “She is insulting civil servants, the vice president, at public rallies. They are denigrating the army - those are the charges.”
The 93-year-old will also be accused of failing to implement the constitution and his age will be used to suggest he no longer has the capacity to rule.
When the impeachment motion is proposed a committee will be set up to investigate it.
At least two-thirds of members of both chambers of Zimbabwe’s parliament will need to back the motion if it is to pass.
The nation’s vice-president would automatically takeover after impeachment proceedings were completed, but the military is thought to favour Mnangagwa.
Vice-president Phelekezela Mphoko is a known supporter of Grace Mugabe.
Grace is under investigation herself following allegation she has embezzled money for the luxurious spending that has earned her the nickname “Gucci Grace”.
The dictator’s refusal to step down has prompted neighbouring Zambia to demand his exit.
Zambian president Edgar Lungu has sent former president Kenneth Kaunda to the capital of Harare in an attempt to convince Mugabe to step down in a "dignified exit”.
It is hoped that Dr Kaunda, who is also 93-years-old and served as Zambia’s first president, will be able to convince Mugabe to end his presidency peacefully and quickly.
A senior government source said: "Dr Kaunda used the presidential jet and has already arrived in Harare.”
Dr Kaunda has openly condemned some of Mugabe’s past actions as president and has backed Morgan Tsvangirai, the leader of the opposition, to be a success should he win the presidency.