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.
A ceasefire has de-escalated the conflict with the Houthis in recent years and led to a freezing of the front lines. But the Saudi-backed ruling coalition – the Presidential Leadership Council (PLC), formed in 2022 and designed to unite various anti-Houthi factions - has frayed.
Meanwhile, the vast majority of southern Yemen has been taken by UAE-backed separatists, the Southern Transitional Council (STC), which is formally part of the coalition.
The infighting escalated on 2 December, when the STC - which seeks an independent state in the south - launched a large-scale military offensive in the east of the country and rapidly took control of territory from government forces. The STC's advances included the oil-rich Hadramawt province that borders Saudi Arabia.
The STC's actions were condemned as a rebellion by PLC head Rashad al-Alimi, who asserted that the STC's drive for separation threatens Yemen's stability.
Tensions have further grown with airstrikes by the Saudi-led coalition, leading to casualties among STC forces. On Friday, seven people were killed in an air strike on an STC military camp in Hadramawt.
The STC has asserted that its military campaign is necessary to "restore stability," but the conflict continues to raise alarms over potential famine and humanitarian crises in a country already ravaged by war.
Despite the UAE's denial of involvement in supporting the STC's offensive, it has agreed to withdraw its forces from Yemen amid mounting pressure from Saudi Arabia. The UAE's motivations for supporting the STC are seen as aimed at securing control over strategic ports and challenging Islamist factions in the region.
The potential for escalation poses serious risks not only for Yemen but for regional stability as a whole.
