HARARE When Zimbabwe's veteran president Robert Mugabe suavely hosted journalists at State House on the eve of last month's election, there was only one question that caught him off guard.
Asked if the presence of Defense Minister Emmerson Mnangagwa by his side meant that he was his chosen successor, Mugabe paused awkwardly amid laughter and then delivered an unconvincing reply that Mnangagwa just dropped by to see him.
Three weeks after Mugabe's re-election in a disputed vote called a fraud by his main rival but accepted by his African neighbors, there are no doubts Africa's oldest leader is holding firmly on to the presidency after 33 years in power.
But the question of whether, at 89, he can serve out all of his new five-year term - and who will succeed him if he steps down or dies - will hang uncomfortably over his re-installation as Zimbabwe's head of state on Thursday.
It will also be crucial for the future of the southern African nation, which is rich in platinum, gold and diamonds but still emerging from a decade-long recession brought on by political violence and government-backed land seizures.
Mugabe faces few immediate threats. Longtime rival Morgan Tsvangirai has been stunned by the enormity of his defeat in an election he says was rigged from start to finish; last week he dropped a challenge to Mugabe's re-election that his Movement for Democratic Change had filed in the Constitutional Court.
The court confirmed on Tuesday that Mugabe's win was "free, fair and credible" and had reflected the "will of the people".
Faced with a meek but broad endorsement of the result by African regional and continental bodies, Western governments must now decide whether to shun the man they have reviled as a ruthless dictator for years, or attempt a rapprochement in the interests of practical diplomacy.
Mugabe's non-committal answer on the succession is typical of a wily and inscrutable guerrilla politician who fought a liberation war leading to independence in 1980, crushed a revolt once in power and has outfoxed rivals in and outside his fractious ZANU-PF party.
Mugabe comes across as feisty and sprightly for his age. He has denied reports that he has prostate cancer and told reporters he intends to serve his full new term.
But his advanced years and the persistent questions about his health, compounded by successive medical check-up visits to Singapore, means that his endurance in office carries its own cloud of uncertainty for Zimbabwe's future.
"Mugabe and Tsvangirai have fought their last elections ... one way or another. Whether it was stolen or not, this was a historic election that prefigures change," Stephen Chan, Professor of International Relations at London's School of Oriental and African Studies, told Reuters.
The United States, a major critic of Mugabe, has made clear it does not believe his latest re-election was credible and that a loosening of U.S. sanctions on Zimbabwe "will occur only in the context of credible, transparent and peaceful reforms that reflect the will of the Zimbabwean people".
The European Union, which had eased some sanctions, is considering its own response after expressing concern about alleged irregularities and lack of transparency in the election.
Adding to Zimbabwe's uncertain outlook is the perception that another Mugabe term will intensify a succession battle within the ruling party. ZANU-PF has a history of feuds and splits dating back to its bush war against white minority rule in what was then Rhodesia.
"Vicious faction-fighting is in the DNA of ZANU-PF," said Stephen Ellis, a professor at the African Studies Center in Leiden, the Netherlands.
Defense Minister Mnangagwa, a 66-year-old guerrilla war veteran and Mugabe's main security enforcer, is widely seen as a succession contender, along with Vice President Joice Mujuru and State Security Minister Sydney Sekeramayi.
Mnangagwa, known as "the Crocodile", earned a hardline reputation as security minister in the 1980s for his role in suppressing rebels in the western province of Matabeleland. Human rights groups say about 20,000 civilians were killed in the crackdown led by the army's North Korean-trained Fifth Brigade.
Mnangagwa, Mujuru and Sekeramayi have been members of Mugabe's cabinet since 1980, and played a major role in ZANU-PF's re-election machine.
During campaigning, Mujuru addressed rallies, Mnangagwa acted as Mugabe's presidential election agent and Sekeramayi was the ruling party's point man for the legislative elections in which ZANU-PF was declared the overwhelming winner.
On the face of it, Mujuru, 58, another liberation war veteran whose nom de guerre was Teurai Ropa ("Spill the Blood") appears to hold an advantage in the succession stakes because as first party vice president she acts for Mugabe when he is away.
But under a new constitution adopted earlier this year, ZANU-PF would choose a new president if Mugabe stepped down or were to die before the end of his term. Many fear this could lead to a scramble for power among ambitious aspirants.
"For all Mugabe's problems, he has been able to keep the peace in ZANU-PF, and has commanded the authority to keep a potentially chaotic party organized," Zimbabwean political analyst Eldred Masunungure said.
"Mugabe's absence could lead to chaos because he has managed the party in such a manner that nobody else has his kind of unquestionable authority," he added.
MNANGAGWA VS MUJURU
Some party insiders say Mugabe has skillfully played the Mujuru-Mnangagwa rivalry to strengthen his own position.
Nine years ago, when Mnangagwa appeared headed for election to the ZANU-PF vice presidency with the backing of six of the country's 10 provincial party structures, Mugabe stepped in to engineer Mujuru's appointment to the job.
There was speculation at the time that Mugabe penalized Mnangagwa for his leadership ambitions and that Mujuru's husband, ex-army commander Solomon Mujuru, had prevailed on the president to promote his wife.
This week, breaking with party tradition that individuals do not actively promote themselves for leadership, Mujuru attacked party rivals and presented herself as the moderate leader ZANU-PF needs after Mugabe, local media reported.
"We know that the president will soon be 90 and God might decide to call him ... I am best placed to succeed Mugabe if he departs whether by natural wastage or voluntary retirement," she told a private weekly newspaper in surprisingly frank comments.
ZANU-PF insiders say Mujuru may have been frustrated by Mugabe's statement that he plans to serve his full term to 2018.
Far from mellowing his anti-Western and nationalist rhetoric, Mugabe has told his critics since the election to "go hang" and promised to increase the pace of "indigenization" policies forcing foreign-owned firms to sell majority stakes to black Zimbabweans.
John Campbell, an Africa expert at the New York-based Council on Foreign Relations, said he saw Zimbabwe going into "a holding pattern", with little prospect of significant economic and political change until Mugabe disappears from the scene.
"I don't think anything will be settled until he's gone," said Tawana Shomwe, 35, who sells recharge cards for mobile phones on the streets of Harare.
(Additional reporting by MacDonald Dzirutwe in Harare and Pascal Fletcher in Johannesburg; Editing by Pascal Fletcher and David Stamp)