The United Nations has warned about the "extreme risk" of large-scale violence in the Democratic Republic of Congo amid a deepening political rift over President Joseph Kabila's future.
Tensions have risen after it has become increasingly apparent that Kabila will stay in office after his term expires in December.
UN special representative for Congo Maman Sidikou said on Tuesday that parties on all sides appear increasingly willing to resort to violence to achieve their ends.
"If this trajectory continues, I believe large-scale violence is all but inevitable," he told the United Nations Security Council.
In September, a wave of deadly clashes pitting police against demonstrators rocked the capital Kinshasa as the opposition demanded Kabila's resignation.
At least 49 civilians were killed in the clashes. Sidikou said 38 people were killed by gunshot, while others were burned alive or killed by machete.
The UN, he said, has documented the involvement of Kabila's presidential guard in the violence, but "non-state actors" were also to blame.
Sidikou heads the UN mission of 22,000 troops in Congo. He warned that UN peacekeepers would be unable to protect civilians if the DR Congo descends into all-out violence.
"The scope of the threats dramatically outstrip the mission's capabilities," he said.
"The coming period will certainly be extremely difficult, the tipping point in the serious violence could be reached very quickly," he added.
Kabila, in office since 2001, is barred by constitutional term limits from standing for a third term but the opposition is accusing him of manipulating the electoral system to stay in power.
The country's electoral commission says November's scheduled presidential vote wouldn't be possible until 2018, and a court has said Kabila can stay in power until the next election.
Opposition parties have called for restructuring the electoral commission and the Constitutional Court, saying they are partisan to Kabila, who came to power after his father's assassination in 2001.
Sidikou urged the UN to encourage all parties currently boycotting the electoral process to return to dialog and ask the government to take confidence-building measures with the opposition.
He also said regional organizations, including the African Union, should work with the UN to engage more directly and designate a high-level emissary to bridge political divisions.