Why was the UN sidelined in "joint" DRC operation against rebels?

 
This week, a long-awaited military offensive began against a Rwandan rebel group
based for the past two decades in eastern Democratic Republic of Congo. It had been
planned as a joint operation between Congolese government forces and a unique
combat unit of United Nations peacekeepers. But by the time the gunfire began on
Tuesday, the partnership had broken down and the UN had been side-lined. full report
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