The M23 rebels took control of a town 100 kilometres (60 miles) from the provincial capital of Bukavu despite a ceasefire.

The city of 2 million people is at the heart of a region home to trillions of dollars in mineral wealth and remains in rebel control.

Rwanda, which diplomats say backs M23 fighters who seized Goma in Democratic Republic of Congo this week, called on Wednesday for a ceasefire across eastern Congo and for Congo to negotiate with the rebels while denying Rwandan troops were involved.