A group of Congolese opposition candidates have written to the governor of Kinshasa to say they will hold a protest next week over the country's disputed presidential election, Reuters reports.

Delays during Wednesday&039;s election day in Democratic Republic of Congo led to an extension of the voting, which some opposition candidates and independent observers said compromises the credibility of the vote.

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Election disputes often fuel unrest in Congo and risk further destabilising a country with globally important reserves of cobalt and copper, which is already battling widespread poverty and an eastern security crisis.

Five opposition candidates plan a joint protest in the capital on December 27, according to a December 22 letter to the Kinshasa governor shared on X social media platform by Jean-Marc Kabunda, a representative of candidate Martin Fayulu.

"We will protest against the irregularities observed during the voting operations ... and before. We will also protest against the (voting) extension," the letter said.

"The aforementioned irregularities sufficiently demonstrate that on December 20, 2023, the elections were a sham," it added.

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The Ceni election commission has acknowledged there were delays on December 20 that meant some polling stations failed to open, but it has rejected allegations the credibility of the election was compromised by extending some voting.

Full provisional results of the election are expected by December 31, with daily updates released from Saturday.