At least six people have been killed in violence in the run-up to the December 23 election, which will see the conflict-ridden central African country emerge from President Joseph Kabila's 17-year rule.

Kinshasa denies any link between the bloodshed and campaigning.

The Security Council asked all sides "to continue to reject violence of any kind, exercise maximum restraint in their actions and ... refrain from provocations such as violence and violent speeches and to address their differences peacefully," a UN statement said.

The members also underscored the importance of ensuring the safety and security of candidates and voters during the campaign period.

Meanwhile, they reiterated their call on all parties to engage peacefully and constructively in the electoral process, to ensure transparent, peaceful and credible elections.

"While welcoming the progress in the technical preparation of the polls, the members of the Security Council are worried about" incidents of violence marring the final days the electoral campaign, the statement added.

As such, the council "calls on the DRC government to quickly investigate these events," it said.