Yemeni separatists over the weekend seized key government and military posts in Aden – the de facto capital – raising the prospect of the South seceding. The power grab, carried out by UAE-backed forces, calls into question the unity and purpose of the Gulf Arab coalition in Yemen, launched in 2015 to restore the Yemeni government to power and roll back gains made by the Houthi rebels.

The Iran-backed Houthis, who seized control of the capital Sanaa and vast swathes of northern Yemen in 2014, remain firmly in control despite years of air raids and blockades.

And now, Southern forces appear in the process of pulling a similar move, capitalizing on the UAE drawdown from a war it has come to see as a quagmire and PR headache.

“Don’t threaten to target us with warplanes. The Houthis held up five years,” proclaimed separatist leader Hani bin Breik on Sunday, addressing an audience in Aden following a sermon for Eid al-Adha (the Muslim Feast of Sacrifice).

The airstrikes arrived anyway, raising alarm among humanitarian organizations struggling to cope with the latest crisis.

“Aden is still recovering from the Saudi-led coalition bombing campaign of 2015,” the International Committee of the Red Cross said.

“A new bombing campaign in Aden will dismantle any progress made since 2015 to reestablish basic services like water and sanitation, healthcare and education, and will further exacerbate what is already the world’s largest humanitarian crisis,” it added.

The latest escalation, the Red Cross warned, threatens a new “war within a war.”

Saudi, UAE mismatch

The power grab in Aden elicited rapid condemnations from senior Saudi officials, who last month were blindsided by their ally the UAE’s drawdown.

“The Kingdom calls on the Yemeni leaders in Aden to respond to (…) prioritize Yemen’s national interest, and immediately withdraw from all positions it seized in Aden,” tweeted Foreign Minister Adel al-Jubeir.

The Yemeni Foreign Ministry called out not only the Southern Transitional Council, but its backer the UAE by name.

“[The] Govt of #Yemen holds the @STCSouthArabia and the United Arab Emirates fully responsible for the coup perpetrated against the state in #Aden,” it said.

Khalid bin Salman, the Saudi ambassador in Washington and brother of the powerful crown prince, emphasized that the kingdom was still set on a unified Yemen:

“The Kingdom’s stance in support of the legitimate government and the unity and stability of Yemen remains unchanged,” he tweeted.

There were no indications that STC forces had budged from their new hold on the city on Monday, despite Saudi-led strikes. Reports of a withdrawal appeared designed only to assuage Saudi Arabia.

The UAE, one Yemen analyst said on condition of anonymity, did not so much give a green light to its allies, but refrained from stopping them.

“The question is where things go from here,” the analyst said. With the Southern forces holding key front lines against the Houthis, and government forces incapable of holding the city, it is unlikely the coalition will make a major push to take back Aden from its official allies.

That leaves Yemen de facto divided, with Houthis in the North, separatists in the South, and a number of loyalist bastions like Maarib in the center.

“I am skeptical you can put it back together, and even if you do, is it worth it?” the analyst said.

For the Emiratis, it is clearly not.

Facts on the ground

For the UAE, a divided Yemen – with the Houthis controlling the north, and allied militias holding sway in the South – could be an acceptable solution to the conflict.

For the Saudis – who share an 1,800-kilometer border along Yemen’s North – a divided Yemen with Houthis on their border would be a threat.

That mismatch facilitated the weekend’s power grab. With the UAE distancing itself from the coalition, the Saudis are now left with few options outside the negotiating table.

The Houthis, as separatist leader Bin Breik pointed out on Sunday, played the long game and succeeded in making their northern takeover a reality. Now it appears the STC is poised to do the same.

It would not be the first time Yemen has been divided. From the 1960s to 1990, the country was split between a socialist republic in the South and the Yemen Arab Republic in the North.

On Sunday, the Red Cross urged the warring parties to sit down and negotiate the future of the country to avoid further bloodshed.

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