Didymus Mutasa, the powerful No. 3 official in Mugabe's ZANU-PF party, said Mugabe's succession was now off the agenda, according to the newspaper, a government mouthpiece.
"There is absolutely nothing to talk about the succession issue any more for the next six years because we shall have the president as our leader. He is not going to be succeeded for that period," Mutasa was quoted as saying.
Mutasa acknowledged two main factions in the Zimbabwe African National Union-Patriotic Front had vied for supremacy over who would replace 83-year-old Mugabe. But he said both factions now "closed ranks" behind Mugabe's continued role as president.
The party agreed Mugabe could not leave when he was needed by both the party and the nation facing what he described as "difficulties," Mutasa said, according to the newspaper.
"So it was quite right of him (Mugabe) to say: ... 'I am not going away, I cannot be running away from a burning house. I should stay and put out the fire,' " Mutasa was quoted as saying.
He insisted Mugabe's decision to stay on until at least 2013, when he would be almost 90, did not leave the party divided.
"As trained and loyal liberation fighters, everyone was rallying around the incumbent leader," Mutasa said in an interview with the state media, the Sunday Mail reported.
The tenor of Mutasa's remarks was reminiscent of several previous occasions when Mugabe, Mutasa and other close loyalists clamped down on calls within the party for Mugabe, the only ruler since independence in 1980, to step down.
In 2004, the ruling party faced its deepest split over Mugabe's choice of Joyce Mujuru, wife of the influential former army commander Gen. Solomon Mujuru, as the nation's second vice president. She became the first woman in the post and effectively blocked former Parliament Speaker Emmerson Mnangagwa's place as first in line to replace Mugabe.
Mugabe railroaded Mujuru into office but last year relations between the two cooled as Gen. Mujuru became increasingly critical of Mugabe and the couple's faction strengthened against Mnangagwa's group.
Mugabe's critics blame him for the southern African nation's economic meltdown, citing mismanagement, his failure to curb high-level graft and for sanctioning state-orchestrated violence against opponents, including the assaults by police and the hospitalization of opposition leader Morgan Tsvangirai, and scores of opposition activists in recent weeks.
Official inflation is running at 2,200 percent and Zimbabwe faces acute shortage of hard currency, gasoline, food and most basic goods.
Five-yearly parliamentary and presidential polls are scheduled next March and there had been suggestions Mugabe might later step down after winning a clean sweep against the fractured opposition, making way for at least fresh economic reforms.
The Sunday Mail sold briskly on the streets of Harare on Sunday.
"Six years? God help us. I don't know how much more of this can we take?" said one businessman at a news stand who asked not to be identified.
It is an offense in Zimbabwe, punishable by jail, to publicly insult Mugabe.