Five years ago, Saudi Arabia rushed headlong into Yemen’s civil war, seemingly without considering the consequences of its action. Five years later, it appears Saudi Arabia seems determined to extricate itself from Yemen, raising concerns that it is failing to weigh the consequences of its withdrawal any more carefully than it did its intervention.

Since last fall, the Saudis have been engaged in direct talks with Ansar Allah, the Houthi insurgent group whose alarming advance across much of Yemen in early 2015 prompted the intervention of an Arab military coalition assembled by Riyadh. While the talks produced a welcome diminution of violence in Yemen in late 2019, in recent weeks, the war has seen an alarming resurgence as Houthi ground forces have advanced in areas of northern Yemen previously considered out of their reach.

These advances, coupled with the fact that the Saudi-led coalition is fragmented internally, add credence to the view that the Houthi rebels have already won the war. In such a circumstance, the rebels will be far less inclined to offer concessions, complicating Riyadh’s efforts to make a face-saving withdrawal. The insurgents control the reins of government and the capital, Sanaa. They exercise unchallenged authority over the majority of Yemen’s 30 million people, most of whom live in the strategic northern highlands. The degree of military superiority they enjoy allows them, as they have in recent weeks, to outmaneuver and outgun forces loyal to the U.N.-recognized government of exiled Yemeni President Abd Rabbu Mansour Hadi. According to Yemeni analyst Nadwa Al-Dawsari, “the Houthis’ military move is strategic,” and coupled with offensives underway in the south and west of Yemen, might enable the group “to expand its control throughout the entire country again.”

Even as the war threatens to engulf areas of Yemen that, until now, had been relatively calm, Saudi negotiators continue efforts to strike a formula with their Houthi counterparts to secure the kingdom’s southern border, which is fundamental to Riyadh’s ability to end its military involvement in Yemen. Failure to achieve its other goals, which include the restoration of the Hadi government and a sharply diminished Iranian role in Yemen, can likely be finessed. In the first instance, President Hadi is widely perceived as being incapable of ruling Yemen. It is only U.N. Security Council Resolution 2216 (2015) that has enabled Hadi to maintain his position, since it explicitly recognizes, “the legitimacy of the President of Yemen,” while making specific demands of the Houthis. The insurgents, invigorated by recent battlefield successes, are likely to find these demands even less tempting than they did five years ago.

As for Iran, the Saudis may be counting on the Houthis concluding that Riyadh is better placed to offer the rebels what they need in the long run than a harried, economically feeble Iran. As Yemeni analyst Abdulghani al-Iryani has noted, the population of Saada, the Houthis’ traditional home base in northwest Yemen, “has always been connected to Saudi Arabia. For generations, Saada has been part of Saudi Arabia’s economy. Intermarriages and family links across the border are common. So, the current situation, in which they are now enemies of Saudi Arabia, is exceptional.” Besides, Riyadh could provide the economic assistance needed to rebuild Saada and revitalize its economy. Riyadh can also ensure the Houthis receive a level of representation in any future national unity government commensurate with the control they currently exert over the country.

The challenge for Saudi Arabia, then, is to resist the temptation to cut and run from Yemen without laying the groundwork for a sustainable political solution to reverse Yemen’s disintegration. The alternative, striking a deal with the Houthis that only secures its border, would virtually extinguish prospects of a broader, national negotiation, inviting the most extreme Houthi elements to leverage their recent gains on the ground and pursue a military end to the war.

Such a scenario already seems to be taking shape, as Houthi forces appear poised to launch a ground assault on Marib governorate – the last stronghold of the Hadi government in Yemen’s north. Since the beginning of the year, Houthi forces have been seizing territory in the region, and are reportedly keen to move toward Marib city, the governorate’s capital. A pitched battle for control of this oil-rich and economically resurgent territory would constitute a nightmare for the some 800,000 internally displaced Yemenis who fled to Marib during the war. It could also, as noted earlier, provide the Houthis with a viable path to try to reclaim territory in Yemen’s south that they held at earlier stages of the war, but have since relinquished.

To do so, the Houthis might be inclined to strike a deal with the Aden-based Southern Transitional Council. The secessionist-minded organization has emerged as a force to be reckoned with, thanks largely to the United Arab Emirates. The UAE trained its fighters and provided essential political support that allowed the STC to secure its position in Aden, a development roundly opposed by the Hadi government. The STC’s expanded influence was further cemented in November 2019 with the signing of the Riyadh Agreement, which gave the south equal representation in an Aden-based national government. It also – for the first time – ensured them a place in any future negotiations on the shape of postconflict Yemen.

Ultimately, any such deal that the Houthis might strike with militias and security forces formerly aligned against them threatens to fracture Yemen even more severely. In such a case, the only part of Yemen that might resemble a state would be the rebel-controlled territory in the north, while the rest of the country slips deeper into chaos, as armed groups united by regional, tribal, or political interests fight among themselves for territory and resources.

To prevent this scenario, and the further deterioration of Yemen’s already woeful humanitarian situation, Saudi Arabia needs to remain engaged politically, and the United States is the country that could most likely persuade it to do so. While Washington has been jawboning the Saudis to seek a negotiated end to their involvement in Yemen’s war, it has been reluctant to lean too heavily on leadership in Riyadh, given the number of other issues it perceives it needs Saudi support for – from energy pricing to its “maximum pressure” campaign against Iran. Now would be a good time to draw on some of the trust it has accumulated with Saudi Crown Prince Mohammed bin Salman before momentum shifts decisively back to the battlefield, leading to a continuation of the war and the abject suffering it has inflicted on Yemen’s civilian population.