The cleric says the former president wanted a gradual and smooth transition of power.

Fidelis Mukonori, a Catholic priest who mediated talks with Zimbabwe's former President Robert Mugabe. [Photo: Courtesy]

Zimbabwe's former President Robert Mugabe knew it was "the end of the road" days before he quit.

He also appeared relieved when he signed his resignation letter after 37 years in power, a Catholic priest who mediated talks leading to his ouster said on Sunday.

Fidelis Mukonori, who has known Mugabe for decades, said in an interview with The Associated Press that Mugabe, under immense pressure in his final days as president, wanted a gradual and "smooth" transition of power to Emmerson Mnangagwa, the vice president he had recently fired and who is now Zimbabwe's new leader.

Mugabe had to resort to "Plan B" , immediate resignation, when Mnangagwa did not return from exile in South Africa at Mugabe's request, according to Mukonori.

The interview at the Chishawasha Mission Church east of Harare, the capital, revealed some of the behind-the-scenes manoeuvring at the frantic end of Mugabe's rule, which began with promise after the end of white minority rule in 1980 and unraveled under pressure from virtually all sectors of a society worn down by economic decline, government dysfunction and restrictions on basic freedoms.

Events moved quickly after the military deployed troops in Harare on November 14. The 93-year-old leader resigned a week later, and Mnangagwa was inaugurated on Friday in a joyous ceremony attended by tens of thousands of people.

While Mugabe had realised he could not stay on as president, he clung to the idea he could remain in his post at least until a ruling party congress next month to ensure a "smooth handover," Mukonori said.

He said the president worried that "'they think I'm now resigning in order to stop the meeting, as if I have something to hide.'"

When Mugabe signed his resignation letter, he expressed relief, as though to say, "'It's done,'" the priest said.