Saudi Arabia's foreign ministry has called for Yemen's southern factions to attend a dialogue in Riyadh, after a dramatic turn of events in the south brought Saudi Arabia and the United Arab Emirates into unprecedented direct confrontation.

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 the groups 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.

The Saudi ministry urged a comprehensive conference in Riyadh to bring together all southern factions to discuss just solutions to the southern cause in a statement on social media. Riyadh said the Yemeni government had issued the invitation for talks.

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.

At the same time, 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 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 said the offensive was necessary to restore stability in the south. But it was denounced as a rebellion by the head of the PLC, Rashad al-Alimi, who said the STC's separatist push threatened to fracture Yemen and plunge the region into chaos.

Tensions have further escalated with air strikes by the Saudi-led coalition. On Friday, seven people were killed in an air strike on an STC military camp in Hadramawt. That followed air strikes on Tuesday on the southern port of Mukalla, where the coalition accused the UAE of delivering military equipment to the separatists. The UAE foreign ministry denied these allegations.

The UAE's motivations are seen as helping secure access to key sea ports and challenging an Islamist party in the government. Despite agreeing to withdraw its troops, analysts suggest this will not change the STC's ambitions for independence.

With millions of people in desperate need of humanitarian aid, the situation remains precarious, and the potential for further conflict between Saudi Arabia and the UAE heightens fears for Yemen’s future.