(AFP) - DR Congo rebuked the African Union on Friday over its calls to suspend the announcement of final results from presidential elections, insisting that the Constitutional Court assessing the vote's legality was impartial.

The court is urgently hearing an appeal over the outcome of the December 30 vote to choose a successor to long-serving President Joseph Kabila, with runner-up Martin Fayulu claiming he was cheated of victory.

"The court is independent, both of us and the African Union," government spokesman Lambert Mende said.

"I don't think it is the business of the government or even of the African Union to tell the court what it should do."

At a summit in Addis Ababa, AU leaders announced late Thursday that they would dispatch envoys to Kinshasa in a bid to end the crisis.

AU commission chief Moussa Faki Mahamat and Rwanda's President Paul Kagame, currently the AU chairman, are expected to fly in on Monday.

The African leaders said there were "serious doubts" about the vote's provisional results.

They called for the announcement of the final results to be suspended -- a matter currently in the hands of the Constitutional Court, which must issue a ruling ahead of the scheduled swearing-in of the next president on Tuesday.

Mende said bluntly: "I don't know if there are countries where people can interfere like that in a legal procedure.

"The court will do what is right for showing the truth. We should all trust it," he said.

In a statement the European Union said it joined the AU in inviting "all the Congolese players to work constructively with this (AU) delegation to find a post-electoral solution which respects the Congolese people's vote".

- Appeal -

On January 10, the electoral commission declared opposition leader Felix Tshisekedi provisional winner with 38.57 percent of the vote against Fayulu's 34.8 percent.

But Fayulu, who has hailed the AU's stance, denounced the figures as an "electoral coup" forged by Tshisekedi and Kabila, and filed an appeal with the Constitutional Court a day later.

He claims he won with 61 percent of the vote.

The Financial Times and other foreign media have reported seeing documents that confirm Fayulu as the winner.

"If the court declares Tshisekedi victor, the risk of isolation would be enormous and untenable for a country positioned right in the middle of the continent," wrote Adeline Van Houtte of the Economist Intelligence Unit on Twitter.

Fayulu's camp hailed the AU appeal for the final result to be put on hold, but Tshisekedi's entourage lashed it as "scandalous."

And his lawyer and deputy chief of staff Peter Kazadi denounced the AU's appeal as having "no legal basis."

It was, he said, the result of manoeuvering by "a small number of countries," which he did not name, and "shamed the institution" of the AU.

- Fears of violence -

The dispute has raised fears that the political crisis that began when Kabila refused to step down at the end of his constitutional term in office two years ago, could turn into a bloodbath.

The vast and chronically unstable country lived through two regional wars in 1996-97 and 1998-2003, and the previous two elections, in 2006 and 2011, were marred by bloody clashes.

The AU has taken the firmest line of all major international bodies with regard to the post-election crisis.

The Southern African Development Community (SADC), a bloc that includes Angola and South Africa, initially called for a recount and a unity government.

But in a later communique, it made no mention of those demands, instead calling on Congolese politicians to "address any electoral grievances in line with the Democratic Republic of Congo's Constitution and relevant electoral laws".

Kagame's visit as part of the AU delegation could complicate matters, analysts say.

Rwanda backed the 1997 ouster of dictator Mobutu Sese Seko by Kabila's father, Laurent-Desire Kabila, but then changed allies. Sporadic clashes occurred last year on the border between the two neighbours.

"I doubt Kagame's credibility, given his qualities as a democrat," Kazadi said.

© Agence France-Presse