Top United Nations officials in Africa have warned an emergency meeting of the U.N. Security Council that the offensive of Rwanda-backed rebels in mineral-rich eastern Congo is threatening peace in the wider region.

The U.N. Security Council has urged Rwanda to halt its backing of the M23 rebels in eastern Congo, insisting on troop withdrawal and renewed diplomacy. Allegations of mineral exploitation by rebels and Congo's use of FDLR fighters have complicated efforts for regional stability.

M23 rebels in the Democratic Republic of Congo have captured the eastern city of Bukavu with the backing of Rwandan forces, the second major city in the mineral-rich Kivu region to fall in three weeks.