HARARE, Zimbabwe (CNN) -- Zimbabwe's opposition said Sunday that it will not "commit political suicide" by entering into a government with President Robert Mugabe without the power to deliver change, food and jobs.
Zimbabwe President Robert Mugabe, in a speech to supporters Saturday, refused calls to step down.
Movement for Democratic Change spokesman Nelson Chamisa made that comment after his party's national executive meeting and ahead of talks slated for Monday on forming a government of national unity.
Last September, Mugabe and MDC leader Morgan Tsvangirai signed a power-sharing deal, but they have not formed a government of national unity.
The agreement, brokered by former South African President Thabo Mbeki on behalf of Southern African Development Community (SADC), stalled as Tsvangirai accused Mugabe of grabbing all key ministries such as defense, information, foreign affairs, finance and home affairs.
South African President Kgalema Motlanthe, chairman of the regional body SADC, is coming to Zimbabwe Monday with his predecessor, Mbeki, and with Mozambique leader Armando Guebuza to try to resolve the impasse.
In an interview with CNN, Chamisa said of Monday's planned meeting: "We cannot go into positions of authority without the attendant and consequent power to enable us to deliver on change, food and jobs.
"It is an act of political hari-kari, political suicide, and we are not ready to commit suicide yet. We cannot commit political suicide by entering into a government limping and in pain. It's like swallowing poison and we become the victims.
"We are going to insist on the outstanding issues, which are to do with equity of ministries, making sure that we attain the position of governors in line with March 29 election and therefore we are going to insist and stick to our position and we hope Mister Mugabe and ZANU-PF will appreciate the nobility of our very vital position." ZANU-PF is Mugabe's party.
Describing Monday's planned meeting as a "watershed," Chamisa said his party wanted the protracted talks to end.
Mugabe told the state media that Monday's meeting would be the final one, and that he would form a government without the opposition if no agreement was reached.
Chamisa responded by saying: "Mugabe is a failure and cannot dictate pace. If they choose to terminate the talks by their arrogance, let it be, we will not give Mugabe latitude to be funny.
"We are the winners and therefore we should be indicating which issues to deliberate on. So we will not give Mister Mugabe latitude to be funny because there is no time for that, people are suffering."
The agreement, under which Mugabe would remain as Zimbabwe's president and Tsvangirai would become prime minister, follows last June's hotly disputed presidential runoff, which was marred by more than 200 deaths, mainly among opposition supporters. Tsvangirai had won the first round in March, but failed to reached the threshold required.
The deal is seen by many as the panacea to the plethora of problems facing Zimbabwe.
The once prosperous nation is facing its worst economic and humanitarian crisis. Acute shortages of essentials have raised inflation, now the highest in the world.
The United Nations says more than five million people face starvation and there is no food aid. Added to that, a cholera outbreak has claimed more than 2,200 lives as the country fails to import adequate stocks of chemicals to treat the water.
The epidemic has coincided with a strike, now in its fourth month, by doctors and nurses demanding a salary review, more medicines and better hospital equipment.
Tsvangirai returned home Saturday and said he was committed to a power-sharing deal with Mugabe, despite recent threats to abandon the deal. But he vowed that he would not be rushed to join an inclusive government.