The United Nations peacekeeping mission in Democratic Republic of Congo on Tuesday said its troops had made a strategic withdrawal from the eastern military base of Rumangabo, ceding ground in the battle against the M23 rebel group.
U.N. troops have been supporting Congolese forces in the fight against the M23, which launched a new offensive in October and seized the town of Kiwanja last Saturday, breaking months of relative calm.
"We have made a strategic and tactical withdrawal from Rumangabo, in consultation with our partners, to better prepare the next steps together," the U.N. mission, known as MONUSCO, said in a post on Twitter.
It did not provide further details.
The loss of the major military base is a setback for Congo and a further blow to the security outlook in the conflict-hit east. The crisis has also deepened a standoff with neighbouring Rwanda over its alleged support for the rebels, which it denies.
"Its fall is another humiliation for Kinshasa. But it also raises serious questions, once again, of how an extremely small rebellion can do this on their own," said Jason Stearns, founder of the Congo Studies Group, a research institute at New York University.
In August, U.N. experts said they had found solid evidence Rwanda had been interfering militarily in eastern Congo. Rwanda's government has disputed the findings.
Goma, the capital of Congo's North-Kivu province, has been effectively cut off from the upper half of the province since the capture of Kiwanja. More than 90,000 people have fled their homes since fighting resumed on Oct. 20, according to the U.N.
The escalation prompted East African heads of state to hold a joint call on Tuesday and schedule a meeting of their defence chiefs to address the security crisis, the office of Burundi's president said in a statement.
(Reporting by Fiston Mahamba and Djaffar Al Katanty, Writing by Alessandra Prentice, Editing by Angus MacSwan)
