As we enter the sixth year of the Yemeni civil war, a series of events has contributed to heightened instability in Yemen. Infighting between the Southern Transitional Council (STC) and Hadi government has reemerged, and these clashes have left the Riyadh Agreement in jeopardy. Tensions have also surfaced between Saudi Arabia and the United Arab Emirates (UAE), as both countries are competing for spheres of influence in southern Yemen. Meanwhile, the Houthis are exploiting Saudi-UAE frictions to expand their influence in the war-torn country.
On March 15, STC forces, which are aligned with the UAE, closed Al-Ma’asheek presidential palace in Aden and blocked a scheduled meeting of officials from Yemen’s internationally-recognized government. This standoff was followed by the resumption of clashes in Aden between STC and Yemeni government forces in March. These clashes began after the STC-aligned storm brigades raided Camp 20, which is a military base controlled by Saudi-aligned forces.
Although hostilities between STC and Yemeni government forces have not escalated to the scale witnessed in August, STC seizing control of Aden through a military offensive has placed the November 2019 Riyadh Agreement—which institutionalized power-sharing between both factions—in jeopardy. This security crisis can be explained by the UAE and Saudi Arabia’s continued geopolitical rivalry in Yemen, and internecine tensions between the STC and Yemeni government, which fuel violence in southern Yemen.
Even though the UAE officially completed its withdrawal from Yemen in early February, Abu Dhabi has refused to relinquish its sphere of influence in southern Yemen. In spite of its pledge to withdraw from Yemen by October 30, the UAE maintained a residual military presence in strategic areas of southern Yemen, such as Rayyan airport in Mukalla and Balhaf port in the oil-rich Shabwa province. Although the UAE now claims to have withdrawn from these areas, it maintains close ties with the Security Belt militias that oppose the Yemeni government and has repeatedly cited concerns about terrorism to justify a role as an overseer of STC forces. In Socotra, the UAE has used humanitarian aid to gain popular support for its hegemonic ambitions, and the STC successfully established a beachhead on the island when two Yemeni government battalions defected to join its ranks. 
Saudi Arabia has also contributed to the escalation of tensions in southern Yemen. On March 13, Saudi Arabia allegedly directed the Jordanian security forces to prevent the transit of a delegation of senior STC officials to Aden, where they sought to participate in political negotiations. This decision frustrated the STC spokesman Nizar Haitham, who warned of adverse consequences for the peace process, but stemmed from Saudi Arabia’s belief that the UAE was not faithfully implementing the Riyadh Agreement. Saudi Arabia has also countered the UAE’s investments in Socotra with its own development initiatives, which intensified the struggle between both countries for hegemony on the island.
In addition to the clashing geopolitical objectives of Saudi Arabia and the UAE, tensions between the STC and Yemeni government officials continue to impede the Riyadh Agreement’s implementation. The STC insists that the Yemeni government is completely dominated by al-Islah, Yemen’s branch of the Muslim Brotherhood, and senior STC officials routinely allege that al-Islah is covertly aligned with the Houthis.  The perpetration of arbitrary detentions, sexual violence and torture by UAE-backed Security Belt militias has increased hostility towards the UAE in Yemeni government-held areas, and STC efforts to rein in these militias after the completion of the Riyadh Agreement have been unconvincing. The Yemeni government’s exclusive blame of the STC for violations of the Riyadh Agreement, such as the December 5 clashes in Abyan, further undermine the bonds of cohesion that keep the agreement intact.
Although the Yemeni government and STC have failed to enforce the Riyadh Agreement thus far, Saudi Arabia and the UAE still see value in ensuring that the agreement does not completely collapse. In the midst of an oil price war and the COVID-19 pandemic, Saudi Arabia and the UAE wish to prevent a rupture of their alliance, which has already been strained by differing positions on Iran and Syria. Due to the critical importance of the Saudi-UAE alliance, Abu Dhabi Crown Prince Mohammed bin Zayed has leveraged his close personal relationship with his Saudi counterpart Mohammed bin Salman to ease tensions between Saudi Arabia and the UAE over Yemen.
Saudi Arabia’s struggle to contain Houthi forces in the Marib governorate and continued Houthi missile strikes on Saudi cities have increased the need for Riyadh to remain exclusively focused on northern Yemen. The UAE views the Riyadh Agreement as a guarantor of the STC’s inclusion in Yemen’s future peace negotiations, which will amplify Abu Dhabi’s bargaining position, and wishes to avoid the popular backlash that could result from a renewed escalation of its military intervention in Yemen.
In addition, both Saudi Arabia and the UAE are alarmed by Houthi efforts to exploit intra-coalitional frictions over southern Yemen. Iran’s belief that the Riyadh Agreement “legitimizes a Saudi occupation of Yemen,” and willingness to capitalize on discord between Saudi Arabia and the UAE have caused the Houthis to further undermine the stability of this volatile region. On January 7, the Houthis struck a pro-government military installation in Dhale, which killed 12 soldiers. On February 12, the Houthis launched a missile strike on a government-held military base in Abyan, which resulted in the deaths of three Yemeni soldiers. The Houthis have also attempted to court al-Islah supporters to join their struggle against the UAE by alleging that Abu Dhabi seeks to exterminate the Muslim Brotherhood from southern Yemen.
As Saudi Arabia and the UAE both wish to advance their independent agendas in Yemen without risking a major escalation between the STC and Yemeni government, the Riyadh Agreement will likely survive until Yemen establishes a new governance framework. On December 1, Hadi endorsed a federal system in Yemen as the optimal solution to the conflict. Even though south Yemeni separatists are wary of Hadi’s assurances on federalism due to their experiences of marginalization ahead of the 1994 civil war and during the 2012 National Dialogue Congress, Saudi Arabia and the UAE will likely agree to south Yemeni autonomy in some form as a pragmatic solution to prevent a future intra-regional conflict.
In spite of the UN’s calls for a ceasefire in Yemen due to the COVID-19 pandemic, hostilities between the STC and Yemeni government continue to pose a major risk to Yemen’s future stability. Although these tensions are stoked by the competing interests of Saudi Arabia and the UAE, both countries have incentives to preserve the Riyadh Agreement and avoid a major intra-regional conflict in Yemen. Even though hostilities between the STC and Hadi’s coalition could complicate Saudi Arabia and the UAE’s efforts to manage their confrontation in southern Yemen, a federal peace settlement presents the best hope for a long-term reduction of violence on Yemen’s southern front.
Samuel Ramani is a doctoral candidate at the University of Oxford’s Department of Politics and International Relations. He is a regular contributor to the Carnegie Endowment for International Peace, Al-Monitor, the Middle East Institute, and the Washington Post on Middle East affairs. He can be followed on Twitter@samramani2.
The views and opinions expressed in this article are those of the authors and do not necessarily reflect the views of Gulf International Forum.
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