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 neighboring Rwanda over its alleged support for the rebels, which it denies.

(With input from Agencies)