Upholding the official results could spark new violence in a country hoping for its first peaceful, democratic transfer of power since independence in 1960. At least 34 people have been killed since provisional results were released on Jan. 10, the United Nations said.
The AU on Monday will send a high-level delegation to Congo to address the crisis in the vast Central African nation rich in the minerals key to smartphones and electric cars around the world. Its neighbors are concerned that unrest could spill across borders.
Congo government spokesman Lambert Mende called the matter one for the country's judicial bodies, and "the independence of our judiciary is no problem."
The declared runner-up in the Dec. 30 election, Martin Fayulu, has requested a recount, alleging fraud. He asserts that Congo's electoral commission published provisional results wildly different from those obtained at polling stations.
Fayulu welcomed the AU's stance and urged Congolese to support it.
Congo faces the extraordinary accusation of an election allegedly rigged in favor of the opposition. Fayulu's supporters have asserted that outgoing President Joseph Kabila made a backroom deal with the declared winner, Felix Tshisekedi, when the ruling party's candidate did poorly.
The electoral commission has said Tshisekedi won 38 percent of the vote and Fayulu 34 percent. However, leaked data published by some media outlets, attributed to the electoral commission and representing 86 percent of the votes, show that Fayulu won 59.4 percent while Tshisekedi received 19 percent.
The uncertainty has led to some protests. The U.N. rights office in Congo has documented 59 people wounded since provisional results were announced on Jan. 10, along with 241 "arbitrary arrests."
The court could uphold the election results, order a recount or order a new election.
It has until Wednesday to rule, according to Willy Wenga, an expert on electoral law. The court has seven working days, but this week included two holidays and Sunday is not a working day.
It is likely that the court, full of Kabila appointees, will confirm Tshisekedi's victory, said Adeline Van Houtte, an analyst at the Economist Intelligence Unit.
"It will come with the risk of increased instability, which could put a halt on the electoral transition," Van Houtte said in a statement. "However, it would also mean that Kabila will have avoided the worst-case scenario for him," a Fayulu presidency.
Fayulu, a lawmaker and businessman who is outspoken about cleaning up Congo's sprawling corruption, is seen as more of a threat to Kabila, his allies and their vast wealth. Tshisekedi, the son of charismatic opposition leader Etienne who died in 2017, is relatively untested and has said little since the election.
The vote came after more than two turbulent years of delays as many Congolese worried that Kabila, in power since 2001, was seeking a way to stay in office. Barred from serving three consecutive terms, Kabila already has hinted he might run again in 2023.
All of the election results, not just in the presidential race, have been questioned after Kabila's ruling coalition won a majority in legislative and provincial votes while its presidential candidate finished a distant third.
Internet service, cut off in Congo the day after the vote to dampen speculation on the results, still has not returned.
Election observers reported multiple problems, including the last-minute barring of some 1 million voters in the east, with the electoral commission blaming a deadly Ebola outbreak. Fayulu asked the court to declare that the commission violated the constitution by not organizing elections in certain constituencies.
But for some Congolese who campaigned hard for Kabila to step aside, having an opposition figure take power is enough, despite questions about the vote.
Reflecting the yearning for stability, 33 Congolese non-governmental groups and civil society movements on Thursday called on people to comply with whatever the court rules to "preserve the peace" in the interest of "national unity."
Petesch reported from Dakar, Senegal. Associated Press writers Elias Meseret in Addis Ababa, Ethiopia and Jamey Keaten in Geneva contributed.
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