Smoke rises in the aftermath of a Saudi-led coalition airstrike, which targeted what it described as ‘foreign military support’ to UAE-backed southern separatists, in Yemen's southern port of Mukalla on 30 December 2025. Reuters/SABAA TV

A powerful alliance in the Arab world has broken apart. The fight started over Yemen’s future but is now a contest to determine whose vision will lead the region.

Saudi commentator Ahmed bin Othman Al-Tuwaijri did not mince his words in a recent column for Al-Jazeera. The United Arab Emirates, he wrote, has become ‘an Israeli Trojan horse in the Arab world [...] Such imprudence and myopia’.

The broadside is the latest salvo in a surprise rift that has shaken the once seemingly unbreakable alliance between two wealthy Arab Gulf nations, Saudi Arabia and the UAE. For decades, the two neighbours have marched in lockstep on foreign policy. Their shared targets included containing Tehran’s influence in their backyard, opposing political Islam – particularly organisations such as the Muslim Brotherhood – and together propping up their global energy interests. But that bond has abruptly splintered into an open rivalry that now spans the region, from the ports of Yemen to the battlefields of Libya, Sudan and the Horn of Africa.

The break over Yemen

The fuse was lit in mid-December when forces aligned with the Southern Transitional Council, a separatist group supported by Abu Dhabi, launched a rapid offensive into Yemen’s oil-rich Hadramawt province. Backed by Emirati training and funding, Southern Transitional Council militias overran positions held by Saudi-supported troops loyal to Yemen’s internationally recognised government. By 20 December, they had seized the port city of Mukalla and advanced toward the Saudi border, now controlling nearly half of Yemen’s territory. This move was no mere skirmish but a calculated bid to solidify southern autonomy, potentially reviving the independent South Yemen that existed before unification in 1990. For the Saudis, who share a 1,100-mile porous border with Yemen, this was problematic. In a rare public rebuke, the Saudi Foreign Ministry declared the offensive a direct threat to the country’s national security, labelling it a ‘red line’ that demanded immediate intervention.

Riyadh’s response was swift. On 30 December, Saudi warplanes struck a shipment at Mukalla’s port, which the kingdom said contained weapons and vehicles from the UAE destined for the Southern Transitional Council. The Emirates responded that they had never ordered any operations that ‘would undermine the security of the Kingdom of Saudi Arabia or target its borders’.

Hours later, Yemen’s Saudi-backed president voided a defence pact with the UAE and ordered its forces out. By early January, the UAE announced a military withdrawal, denying it had armed the separatists. Soon afterwards, Saudi-backed forces advanced on Aden, the separatist stronghold, prompting defections and the flight of their Emirati-backed leader, Aidarous al-Zubaidi.

Clashing visions

Apart from border security, at the heart of this rift lies another fundamental clash of strategies forged in Yemen’s decade-long civil war. When Saudi Arabia and the UAE launched their intervention in 2015 to oust the Iran-aligned Houthis from Sanaa, they shared a common goal: containing Tehran’s influence in their backyard. But as the conflict dragged on, costing Riyadh billions of dollars, thousands of lives and severe reputational damage, their paths diverged. Saudi Arabia, under Crown Prince Mohammed bin Salman, shifted towards diplomacy, brokering a fragile truce with the Houthis in 2022 and prioritising Yemen’s unity to secure its southern border. The kingdom views fragmentation as a recipe for perpetual instability, potentially allowing either extremists or Iranian proxies to flourish.

The Emirates, on the other hand, prioritised securing strategic maritime chokepoints through pliable, and often cash-strapped, local proxies, dismissing a unified Yemen as inherently unstable. In Yemen, it pursued a strategy of influence, through the Southern Transitional Council, to control strategic ports. Riyadh came to see this not as stabilisation, but as an attempt to reshape the region through division and a land grab within its sphere.

Riyadh quickly transformed the localised spat in Yemen into a broad strategy of containing Abu Dhabi’s ambitious regional plans. The aim has been to prevent the UAE from expanding influence across Africa and the Middle East, something that would threaten Riyadh’s unwritten leadership, particularly after traditional seats of regional power such as Baghdad, Cairo and Damascus, weakened by various crises, have all stepped aside. Saudi Arabia moved to effectively build a coalition by aligning with traditional state powers to choke off the UAE’s network of armed proxies, which Abu Dhabi has spent the past decade cultivating.

In Somalia, Riyadh is working with Egypt in a Red Sea military pact to oppose Emirati-supported separatists, leading Somalia to scrap UAE port and security agreements and block flights carrying Abu Dhabi’s arms deliveries.

In Libya, Riyadh and Cairo have stepped up pressure on warlord Khalifa Haftar to halt aid for UAE shipments to Sudan’s Rapid Support Forces, an ethno-mercenary paramilitary force fighting the Sudanese army.

In Sudan, Saudi Arabia backed the Sudanese Armed Forces against UAE-aligned Rapid Support Forces with a $1.5bn Pakistani arms package.

All this comes against a backdrop of a highly orchestrated Saudi media blitz against the UAE.

The Emirates has also made conspicuous countermoves in this strategic game of chess. The country bypassed the Saudi–Egyptian–Somali blockade by doubling down on support for Somaliland, a breakaway province in Somalia that, to date, is only recognised by Israel, which is quickly shaping up as a staunch UAE ally. The Emiratis are now positioning Berbera as a ‘sovereign hub’ that Riyadh cannot legally touch, effectively reclaiming a logistical foothold in the Red Sea. They further quietly recalibrated strong military support for the Rapid Support Forces in Sudan by establishing new ‘corridors’ through Ethiopia and Chad, two countries that are increasingly siding with the UAE.

This Saudi–UAE rupture is no longer about Yemen alone. It has drawn in several countries and is fundamentally about who sets the rules of power in the Arab world and who shapes the region’s future. ‘The real significance of the Yemen bust-up is that it demonstrates the degree of divergence in Saudi and Emirati visions of regional order,’ says Kristian Coates Ulrichsen, Fellow for the Middle East at the Baker Institute, Rice University, writing in The Conversation. ‘A fractured vision of regional order between the Gulf’s two biggest players does not bode well for the future.’

Emad Mekay is a freelance journalist and can be contacted at emad.mekay@int-bar.org