Yemen's future hangs in the balance after a dramatic turn of events in the south which have brought Saudi Arabia and the United Arab Emirates into unprecedented direct confrontation and threaten the country with partition.
Both Gulf powers have intervened on behalf of Yemen's internationally recognised government in the country's long-running civil war, but a fracturing of the alliance has seen them backing different rival groups on the ground, one of whom is now pushing to declare the independence of a breakaway state in southern Yemen.
On Friday, the UAE-backed force declared that a "war" had begun, accusing Saudi-backed ground forces of launching an attack alongside air strikes by the Saudi air force.
Yemen's civil war broke out in 2014 and has plunged the already impoverished country into years of deadly violence and one of the world's worst hunger crises.
At the start of the war, the Iran-backed rebel Houthi movement took control of most of northern Yemen, including the capital Sanaa, from the government. The conflict escalated in 2015, when a coalition of Arab states including Saudi Arabia and the UAE launched a military campaign to restore the government's rule.
