Opposition leader Felix Tshisekedi was on Thursday declared the victor of DR Congo’s controversial presidential election in a surprise result swiftly denounced by his rival as a “coup”.

In a pre-dawn announcement, the election commission named Tshisekedi, son of the country’s late veteran opposition leader, as provisional winner of the bitterly-contested December 30 vote.

At stake is political stewardship of the notoriously unstable central African nation which has never known a peaceful transition of power since independence from Belgium in 1960.

Tshisekedi’s apparent victory was greeted by celebrations at the headquarters of the Union for Democracy and Social Progress (UDPS), the country’s oldest and largest opposition party which was founded by his father Etienne.

The 55-year-old immediately pledged to work closely with current incumbent Joseph Kabila.

“Today we should no longer see him as an adversary, but rather as a partner for democratic change in our country,” he told supporters.

But the result was immediately denounced by his opposition rival Martin Fayulu, the runner up, who slammed the announcement as “an electoral coup”.

French Foreign Minister Jean-Yves Le Drian said the declared outcome was “not consistent” with the results, saying that Fayulu appeared to have won.

With the vast central African country increasingly on edge over the long-delayed vote to replace Kabila, who has ruled the country with an iron fist since 2001, the United Nations warned against any resort to violence.

“The Secretary-General calls on all stakeholders to refrain from violence and to channel any eventual electoral disputes through the established institutional mechanisms,” spokesperson Stephane Dujarric said late Wednesday.

Kabila had been due to step down two years ago, but managed to cling on to power, sparking an escalating political crisis marked by widespread protests that were brutally repressed, leaving dozens of people dead.

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