The UN Security Council demanded an end to foreign support for rebels closing on a provincial capital in eastern Democratic Republic of Congo.
M23 rebels patrol in Rangira, near Rutshuru, in the Democratic Republic of Congo in October. The UN Security Council demanded an end to foreign support for rebels closing on a provincial capital in eastern Democratic Republic of Congo.
With M23 rebels less than 20 kilometers (12 miles) from Goma, the main city in the mineral-rich region, UN leader Ban Ki-moon appealed to Rwanda's President Paul Kagame to "use his influence on M23," said UN peacekeeping chief Herve Ladsous.
Rwanda has denied a report by UN experts that it has backed the rebels. Ladsous said the United Nations could not confirm whether Rwanda is helping the new rebel offensive but told reporters that M23 "attacking forces are well-equipped and very well supplied."
Human Rights Watch said it has "credible reports" that Rwandan troops have crossed into DR Congo since Thursday.
The Security Council met in an emergency session demanded by France after M23 took another town close to Goma, forcing a high alert in the city of nearly one million people.
A council statement demanded an end to the M23 advance and "that any and all outside support and supply of equipment to the M23, cease immediately."
It vowed new sanctions against M23 leaders and those who help it breach UN sanctions and an arms embargo.
The rebels had night-vision equipment which enabled them to launch Saturday's offensive on Kibumba, and have also recently acquired 120 mm mortars, Ladsous said.
UN attack helicopters fired on the rebels at Kibumba in support of DR Congo forces but could not stop M23 -- mutineers who broke away from the government army in April -- from taking the town, which is 25 kilometers from Goma, Ladsous said.
Government forces are now defending Kibati, 18 kilometers from the capital of Nord Kivu province. Nearby is a camp of between 60,000 and 80,000 displaced people.
"The fear obviously is that those people will flock towards Goma to seek protection if the M23 advances further," the UN peacekeeping chief said.
"The fall of Goma would inevitably be a humanitarian tragedy, with even massacres and civilian panic," said France's UN ambassador Gerard Araud. "That is why we must stop the M23."
The United Nations and the government of the DR Congo have activated a special security plan in Goma which includes protection centers for UN staff, officials said.
There are some 6,700 peacekeepers in Nord Kivu province with some 1,500 troops in Goma.
The DR Congo government has said 4,000 troops had crossed the border from Rwanda to help the M23. The Rwandan government has strongly denied the claim.
However, Human Rights Watch UN director Philippe Bolopion said "we are gathering credible reports from independent witnesses, including alongside the border, that Rwandan troops have crossed into DRC since Thursday morning to support M23 fighters."
UN chief Ban spoke with Rwanda's Kagame on Saturday "to request that he use his influence on the M23 to help calm the situation and restrain the M23 from continuing their attack," Ladsous said.
He also spoke with DR Congo's Foreign Minister Raymond Tshibanda to support the government's efforts to repel M23, said Ladsous.
Araud said France's Foreign Minister Laurent Fabius had been in contact with his Rwandan and DR Congo counterparts.
The United Nations this week ordered a global travel ban and assets freeze against M23 leader Sultani Makenga, a former army colonel. The US government also ordered sanctions.
The sanctions experts have called for Rwanda's defense minister, General James Kabarebe, to be added to the blacklist, diplomats said.