Talks between the government of the Democratic Republic of Congo and a rebel faction taking place in Nairobi have encountered difficulties, with U.N. Special Envoy Olusegun Obasanjo placing most of the blame on the rebel delegation. The rebel group, led by Laurent Nkunda, was also accused by Human Rights Watch of massacring 150 civilians in a town in eastern Congo in early November.

Delegations from the Congolese government and the rebel National Congress for People's Defense have been meeting in Nairobi since Monday, in an effort to halt the latest round of fighting in eastern Congo.

So far the talks have only included preliminary discussions on setting up a framework for further negotiations. But late Wednesday, the U.N.'s Special Envoy to the conflict in Congo, former Nigerian president Olusegun Obasanjo, said progress was going more slowly than he would like, singling out Laurent Nkunda's CNDP rebels for the most criticism.

"Progress has been slower than desired because the power given to the CNDP delegation by its leadership appears to have severely limited its ability to make decisions on matters of concern without continuous recourse to its leadership in North Kivu," he said.

He said the rebel group should either give its delegation more authority, or send another representative. Obasanjo also said the rebel demands were too broad for the current talks, which are focused on eastern Congo.

"The CNDP continues to demand discussions on what it sees as challenges facing the country as a whole," he said. "Not just the ongoing conflict and humanitarian emergency in the eastern DRC."

Obasanjo said the talks have not collapsed, but that he was dispatching a delegation to North Kivu province to meet with Nkunda.

Nkunda's rebels are also the target of a new report by the organization Human Rights Watch that details a massacre of at least 150 civilians in the eastern Congolese town of Kiwanja in early November. The report said most of the victims were killed by Nkunda's forces, though some were killed by the Mai Mai militia which has tended to ally with the government. According to the report, most of those killed were men and teenage boys who the rebels accused of being Mai Mai members.

The organization also highlighted the incapacity of U.N. peacekeepers in the area to halt the fighting. U.N. soldiers were at a base less than a kilometer away, but did not act to protect the town. Stretched thin, and facing logistical difficulties, the peacekeepers focused on protecting civilians who had fled to the base, and on evacuating aid workers. An official with the mission said the peacekeepers were unaware of the massacre while it was happening.

Human Rights Watch says both the CNDP and the Mai Mai continue to commit crimes against civilians in the region, including rapes and recruiting child soldiers. The group called for the European Union to approve the deployment of a temporary force for the region until U.N. peacekeeping reinforcements arrive.

Meanwhile, a draft U.N. report has accused both the DRC and neighboring Rwanda of backing rebel factions in eastern Congo. The report, which is set to be presented to the U.N. Security Council in coming days, reinforces widespread claims that the government of Rwanda has been providing assistance to the CNDP, including providing equipment and helping to recruit fighters. The report also says the Congolese government has backed the Rwandan Hutu FDLR militia.

Both Congo and Rwanda have denied direct backing for militias in eastern Congo. In recent days Congolese officials have threatened to pursue the FDLR.