DUBAI, United Arab Emirates — The attack on Abu Dhabi claimed by Yemen’s Houthi militants Monday threatens to derail fragile efforts at rapprochement between Gulf Arab states and Iran, even as clear attribution for the strikes — which caused fires and fuel tanker explosions that killed three people — is yet to be fully confirmed.

It also could complicate the already challenging negotiations between the U.S. and Iran, the latter of which backs the Houthis financially and militarily, on reviving the 2015 Iran nuclear deal.

The UAE’s government has pledged to hold those responsible for the attack — suspected to have been carried out by drone — to account. Already on Tuesday, the Saudi-led coalition that’s been at war in Yemen since 2015 began carrying out airstrikes on camps and buildings in the capital of Sanaa belonging to Houthi militants, the coalition reported. The strikes around the Houthi-held city have so far killed around 20 people, a Houthi official told Reuters.

But many regional analysts point to what they believe is likely the directing force behind the Houthis’ attack: Iran. The UAE has been a part of the coalition fighting the Houthis since 2015, and though it significantly reduced its forces from the country in 2019, it still trains and supports anti-Houthi groups.

“I think the issue we’ve got to determine, first of all, was it the Houthis directly,” Angus Blair, professor of practice at the University of Cairo in Egypt, told CNBC on Tuesday. “Nothing would have happened without Tehran’s consent or direct engagement.”

Iran’s foreign ministry, commenting on what it described only as “recent Yemen-linked developments,” said Tuesday that “the solution to any regional crisis is not to resort to war and violence.” Its spokesman did not mention the Houthis or the UAE attack, according to Reuters.

While blaming Iran still remains speculative, Iran and the Gulf Arab states support opposing sides of numerous regional conflicts including those in Yemen, Syria and Lebanon. Saudi Arabia has accused Iran of attacking its oil infrastructure and of providing Yemen’s Houthi rebels with missiles used to attack the kingdom, which Tehran has denied. 

Blair and others cite historical example to back up their suspicion. Iran has provided missiles and drones to the Houthis for several years, backing them as part of a broader proxy war with Saudi Arabia, which spearheaded an aerial assault on Yemen beginning in early 2015 after the rebel movement overran Yemen’s Saudi-backed government.

In September 2019, the Houthis initially claimed responsibility for a dramatic attack on Saudi Aramco’s massive Abqaiq and Khurais oil facilities in the kingdom, before Saudi and Western authorities concluded the attack had been directed by Iran. Their intelligence agencies found that the Houthis could not have carried out such a sophisticated attack, although Iran has consistently denied the allegations.

“If you look at the attack on Abqaiq in Saudi, initially the Houthis said they’d undertaken it, and very soon afterwards it was clear that the attack had come from Iran,” Blair said. ”So we have to make sure first of all that this was the Houthis.”

The strike on Abu Dhabi, which hit a fuel storage facility of state oil company ADNOC, came amid renewed fighting in Yemen. UAE-backed Yemeni militia fighters recently forced the Houthis out of the oil-rich area of Shabwa and pushed back their advances in the key governorate of Marib, home to the bulk of Yemen’s oil, without which the Houthis are unlikely to survive as a state.

News emerged in late 2021 that Riyadh and Tehran had begun exploratory talks, an effort crucial in easing regional tensions, particularly with Iran’s new hardline government. While Riyadh and Tehran have not conveyed any expectations of a major breakthrough, both sides have expressed support for easing tensions, and the Biden administration said it welcomed the outreach.

Any progress on that front may be stalled now.

“It seems likely this will cause at least a temporary setback between the GCC and Iran talks,” Ryan Bohl, a Middle East and Africa analyst at Rane, told CNBC. The key question then is whether the UAE decides to point the finger of blame for the attack at Tehran, which it avoided doing over a series of tanker sabotage blasts off its coast in 2019 that Riyadh and Washington squarely blamed on Iran.

“It will remain to be seen if the Emiratis decide to hold Iran responsible or if they do what they’ve done in the past which is overlooked the Iranian role in order to avoid escalation,” Bohl said. “The Emiratis are likely to compartmentalize the retaliation to Yemen at least in the short term.”

Monday’s attack, the biggest in the country that has been claimed by the Houthis and the first since 2018, “highlights the UAE’s vulnerable geopolitical position and their role in the war in Yemen, neither of which are ideal for the country’s national and business reputation,” Bohl said.

ADNOC, the site of the alleged drone strikes, said that it had “activated the necessary business continuity plans to ensure the reliable, uninterrupted supply of products” to its customers. But the fact that aerial attacks were able to take place so close to both oil facilities and Abu Dhabi International Airport, near where one fire also broke out, was a warning sign to many observers. Drones present such a threat because they are generally not picked up by radar and other air defense systems.

The event “is another reminder of the highly complex missile and drone threat faced by the UAE and the region’s other main oil producers,” Torbjorn Soltvedt, principal MENA analyst at Verisk Maplecroft, wrote in an analysis note Monday. “Unless the Gulf Cooperation Council states can find a solution to diffuse regional tensions, or deter hostility from regional state and non-state actors, they will remain vulnerable to attacks.”

Emirati officials deny that their country’s reputation as an isle of stability in an otherwise volatile region is being threatened. Anwar Gargash, former UAE minister of state for foreign affairs, wrote on Twitter on Tuesday: “Terrorists militias’ tampering with the stability of the region is too weak to affect the security and safety we live in.”

As for the Houthis, the group has published propaganda videos threatening to make the UAE an “unsafe place” and has pledged to continue their operations against the UAE.

“The Houthis have shown that they will hold the UAE responsible for the actions of its proxy units,” veteran Middle East journalist Gregory Johnson wrote on Twitter. This could draw the UAE back into more fighting in Yemen, or spur increased airstrikes on Houthi-held territory.

Still, Bohl says, “By limiting the retaliation to Yemen,” rather than extending it to Iran, “the potential for major escalation is reduced even if it does put the UAE into a tricky position of establishing credible deterrence against the Houthis … As well as reminding the international community that the UAE is still very much active in Yemen, despite its much publicized so-called withdrawal in 2019.”