Democratic Republic of Congo's powerful Catholic Church has said it knows who has won a much-delayed presidential vote and urged the electoral commission to publish the "truth".

The appeal from the National Episcopal Conference of Congo (CENCO) came hours after the election commission said logistical problems may force it to postpone publication of provisional results from Sunday's ballot.

CENCO spokesman, Father Donatien Nshole, said: "Data in (CENCO's) possession from the vote counting reports from polling stations designates the selection of one candidate as president."

It called on the election panel "to publish the election results in keeping with truth and justice," he said.

Western powers and DRC's neighbours hope sub-Saharan Africa's biggest country will see its first peaceful transition of power since independence in 1960.

The US demanded that "accurate" election results be released, warning of sanctions against anyone who undermined the fledgling democracy.

The US also called on the DRC authorities to remove restrictions on internet access and media and urged the Independent National Election Commission (CENI) to count votes in a transparent way.

The US State Department spokesman, Robert Palladino, said in a statement: "There are moments in every nation's history when individuals and political leaders step forward and do the right thing. This is one of those moments for the DRC."

The UN Security Council will hold a closed-door meeting today, requested by France, about the elections. The council is scheduled to hold a public meeting next Tuesday.

The French public-service broadcaster, Radio France Internationale (RFI), which has a huge following in DRC, said its correspondent, Florence Morice, was forced to leave the country on Thursday night, after having her accreditation revoked.

Congolese authorities have blocked RFI's broadcasts after accusing it of fanning controversy by declaring early results, an allegation it denies.

President Joseph Kabila, 47, should have stepped down at the end of 2016 when his constitutionally-limited two terms expired.

President Kabila has been in power since 2001 

But he invoked a caretaker clause in the constitution to stay on, sparking protests that were ruthlessly crushed, leaving scores dead.

Elections to succeed him were delayed several times before they finally took place, and were further postponed in several areas hit by violence.

Tension has risen further over the marathon counting process with opposition fears running high that the result will be rigged to favour Mr Kabila's preferred successor, Emmanuel Ramazani Shadary.

CENCO said it deployed more than 40,000 observers to monitor Sunday's vote, the first presidential ballot since 2011.

Monitors noted some "irregularities" in Sunday's voting, but Fr Nshole said: "They were not able to significantly affect the choice which the Congolese people clearly expressed through the ballot box."

The election commission, CENI, has scheduled to announce the provisional results on Sunday, followed by the definitive results on 15 January and inauguration of the next president three days later.

However, the head of CENI, Corneille Nangaa told the AFP news agency that provisional results may be delayed, saying: "We are working ‘round the clock. We are doing our best to publish the results on 6 January. But if we can't, we can't."

He later told a news conference that election officials had collected about 20% of the results needed and that results from all 73,000 voting stations would then be consolidated.