Rwandan-backed fighters closed in on eastern Congo's largest city of Goma on Sunday, forcing thousands of civilians to flee and grounding flights from the local airport as government forces battled to stop the rebels seizing the city.

Rebels in Democratic Republic of Congo are closing in on a key city in the mineral-rich region aided by neighboring Rwanda’s army, the head of a peacekeeping mission told United Nations Security Council members during an emergency meeting on Sunday.

Congo has severed diplomatic ties with Rwanda as fighting between Rwanda-backed rebels and government forces rages around the key eastern city of Goma.