Understanding the Saudi Reaction to the Escalation in Yemen

Commentary by Michael Ratney

Published December 31, 2025

Saudi Arabia has responded decisively and forcefully to the recent capture of two southern Yemeni provinces by the Southern Transitional Council (STC), a political organization backed by the United Arab Emirates (UAE), and the subsequent shipment of what it believes to be weapons and vehicles from the UAE destined for STC forces. The STC, whose ideology is both secessionist and anti-Islamist, was established in 2017 with the support of the UAE. Despite its desire to establish an independent "State of South Arabia," the STC had been an integral part of the internationally recognized government of Yemen as constituted in 2022 under the Presidential Leadership Council, which has been supported since its inception by Saudi Arabia and, ostensibly, by the UAE as well. Saudi Arabia reads the STC's moves as UAE-supported preparations to secede from the Yemeni state and declare independence, and it sees the alleged weapons shipment as tangible facilitation of those plans.

In an unusually blunt public statement on December 30, the Saudi Ministry of Foreign Affairs directly called out the UAE, characterizing its actions as a "threat to the Kingdom's national security" and urging the UAE to "accept the Republic of Yemen's request for all its forces to leave the Republic of Yemen within twenty four hours, and halt any military or financial support to any party within Yemen." The UAE quickly issued a rebuttal the same day, denying there were weapons in the shipment and claiming the Saudi statement contained

. . . fundamental inaccuracies . . . regarding the UAE's role in the ongoing developments in the Republic of Yemen. The UAE categorically rejects any attempt to implicate the country in tensions among Yemeni parties and strongly denounces allegations that it exerted pressure on, or issued directives to, any Yemeni party to undertake military operations that would undermine the security of the Kingdom of Saudi Arabia or target its borders.

That statement notwithstanding, the UAE's defense ministry said, also on December 30, that it was withdrawing its counterterrorism units from Yemen, reportedly the only remaining Emirati military forces in the country.

From the Saudi perspective-and despite UAE protestations-there is simply no way the STC would have proceeded with its seizure of territory in Hadramawt and Al-Mahra without a green light from the UAE. For Saudi Arabia, this was the UAE putting the STC ahead of its relationship with Saudi Arabia. Saudi Arabia viewed Emirati-backed forces seizing territory from Saudi-backed forces as a hostile move, particularly when all these forces were supposed to be fighting the same Houthi enemy. And to make matters worse, it saw the UAE as needlessly stoking regional conflict for no explicable purpose.

There have certainly been harsh-perhaps unprecedented-statements over the past several days, but this is much more than a war of words. Saudi forces have now conducted air strikes twice in southern Yemen. On December 27, they conducted strikes-essentially warning shots-in the vicinity of STC forces in Hadramawt province. And on December 30 in Mukalla, Saudi forces reportedly bombed the shipment from the UAE that it alleged included weapons and vehicles. Saudi Arabia claimed the weapons were bound for STC forces; the UAE quickly denied this, claiming that the shipment was only vehicles intended for its own forces in southern Yemen, and that this had all been done in coordination with Saudi and Yemeni government forces.

The Emirati role in all this and the UAE's motivations remain perplexing. Saudi Arabia's impulse to react as sharply as it did was more understandable.

First, Saudi Arabia's whole approach to the region is premised on de-escalation of the region's conflicts, most of which defy any satisfying resolution. Saudi Arabia is nine years into a massively ambitious social and economic transformation and sees the region's persistent conflicts as a principal threat to that effort's success. It is difficult, after all, to convince international investors to risk their money in Saudi Arabia, or tourists to plan their vacations there, while there is conflict on the country's borders, or potentially even rockets and drones targeting Saudi cities. At a time when Saudi Arabia wants de-escalation, it sees the UAE-rightly or wrongly-as stoking regional conflict in a way that will not end well for anyone.

Second, and more specifically, Saudi Arabia views a separatist movement on its southern border as a direct threat to the country's national security. Conflict in southern Yemen, potentially leading to a declaration of independence by the STC, ultimately weakens the internationally recognized Yemeni government and thus benefits the Houthis. A stronger Houthi movement means Iran has a stronger foothold on the Arabian Peninsula. It is also hard to know precisely how a southern secession from Yemen would play out. Would an STC secession lead to infighting among anti-Houthi forces, perhaps even among southerners? Would it encourage the Houthis to attack or try to seize more territory? Would it reduce Saudi influence? All of these are unacceptable risks for the Saudi crown prince, and the uncertainly alone is enough to cause Saudi Arabia to nip the secessionist impulse in the bud. Instead, the Saudi statement argues the "just" southern cause should be resolved through "dialogue within a comprehensive political solution for Yemen."

Third, Saudi Arabia may expect threats to its security from proxy forces backed by a country like Iran, but it is more shocking to experience such threats with backing from a fellow Gulf Cooperation Council (GCC) member, whatever grievances the two countries may harbor. This alone explains why Saudi Arabia's disappointment with the UAE's behavior is so great. For Saudi Arabia, this is not a pattern that can continue without doing damage to the cohesion of the GCC and the group's collective ability to face their genuine common adversaries.

And fourth, Mohammed bin Salman (MBS) will eventually-and maybe soon-become king of Saudi Arabia. Despite the theoretical equality of the six GCC member states, that position is widely seen as a first among equals and, for many, the leader of the broader Arab and Muslim world. This is not a moment when MBS can be seen to be acting in any way but decisively, protecting his own country's national security, maintaining the credibility of Saudi efforts to keep Yemen united, and weakening Iranian influence.

The 2017 Gulf rift that led to the blockade and isolation of Qatar emerged out of similar allegations that Qatar was stoking regional tensions in a way that was antithetical to the Gulf's collective security. That intra-GCC crisis was eventually healed, not because of outside efforts, but because the GCC leaders themselves ultimately found a way to reconcile given the economic imperatives they all shared. This conflict over Yemen is the biggest public crisis within the GCC since then. It seems likely that Saudi Arabia has been trying to resolve this quietly with the UAE over recent weeks. But for Saudi Arabia, the alleged weapons shipment to Mukalla was the straw that broke the camel's back, leading it to air its grievances publicly and undertake military action. This is a dangerous moment for the GCC, and once again, the grouping has a great interest in de-escalating a potential crisis. Each day it goes on is a gift to Iran and other GCC adversaries in the region.

Michael Ratney is a senior adviser (non-resident) with the Middle East Program at the Center for Strategic and International Studies in Washington, D.C.

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