From the perspective of Gulf Arab states, the sudden shift in U.S. policy toward the Ukraine war and Washington’s apparent warming of ties with Russia may be good news. It vindicates their insistence on staying away from the European conflict and maintaining relations with Moscow as part of their foreign policy of multialignment. But even if the ongoing changes in Europe may prove the Gulf gambit right, it hides another parallel development – the evolution of Russia’s Middle East policy as a by-product of its war in Ukraine. This policy directly affects Gulf Arab security interests, at least on two critical issues: Russia’s growing ties with Iran and empowerment of the Houthis in the Red Sea crisis.

In the past three years, Russia and Iran have increased their military cooperation to an unprecedented level. This culminated with the signing of a new strategic partnership during the January visit of Iranian President Masoud Pezeshkian to Moscow. While the announcement was quickly eclipsed by the inauguration of President Donald J. Trump three days later, the agreement has highlighted how far the Russian-Iranian relationship has evolved in recent years.

Though Russian and Iranian officials put the trade dimension of the partnership at the forefront, that relationship includes a significant military component, mainly in arms transfers. This is not new: For a long time, Russia has been the top arms supplier of Iran. Tehran has traditionally relied on Russia for advanced platforms, such as air defense systems to enable Iran to prevent attacks in the event of a U.S. or Israeli campaign. But as the conflict in Ukraine escalated into a war of attrition around 2023, Moscow also relied on Tehran to supply its forces on the battlefield with munitions, artillery shells, and, most important, drones (such as the Shahed-131/136 and Mohajer-6). This Iranian military support enabled Russia to ramp up its missile and drone campaign on Ukrainian cities. In the fall of 2024, the administration of then-President Joseph R. Biden Jr. also reported that Iran had provided Russia with Fath-360 close-range ballistic missiles.

Tehran’s assistance to the Russian war machine in Ukraine offers Iran greater access to Russia’s military and technology industry. For instance, in February 2024, one Iranian satellite was launched into orbit thanks to Russia. There has been intense speculation that Russia might also supply Iran with new air defense systems, the need for which has become critical for Tehran since Israel reportedly destroyed a large bulk of the Iranian defenses during an October 2024 air campaign.

So far, both sides have denied having consultations on this topic. But if the war in Ukraine comes to a halt – at least temporarily through the cease-fire negotiated by the Trump administration – Russia’s defense industry might be able to redirect platforms initially planned for deployment on the Ukraine frontline to Iran. This could include air defense systems, but the Iranian military may be eager to order many other items on the Russian shelves, such as the advanced fighter aircraft Sukhoi Su-35.

In addition to arms transfers, Russia and Iran have held bilateral and multilateral training exercises. In early March, Russia, Iran, and China conducted their fifth annual naval exercise in the Gulf of Oman since 2019.

These developments in Russian-Iranian military cooperation should be alarming for Gulf Arab states as they could challenge the current status quo with Tehran and change the strategic equation in the Arabian Peninsula. If Iran gets greater access to Russian military platforms and technology, it may embolden the hard-liners within the regime in Tehran. The Islamic Revolutionary Guard Corps could then assess that the modernization of its forces reduces its enduring inferiority vis-a-vis Gulf armed forces and allows the IRGC to be more assertive in the Strait of Hormuz.

Gulf states might not fear this scenario at the moment because of the reconciliation process initiated by Saudi Arabia and its neighbors with Iran in past years. However, the current lull between both sides of the Gulf is more the product of a fragile nonaggression pact than a stable cooperation framework.

Furthermore, the deepening of military cooperation between Russia and Iran should alert Gulf states, particularly Saudi Arabia and the United Arab Emirates, which are cultivating their own ties with Moscow’s defense industry. Members of Congress in Washington have expressed concerns about those ties because of suspicions regarding Russian espionage. Gulf states should equally be worried that Iran could use its proximity with Russia to gather information on sensitive technologies used by Gulf militaries.

Russia’s engagement with the Houthis should also raise alarm among Gulf decision makers. Moscow has traditionally kept a neutral stance vis-a-vis the Yemen conflict. Over the years, there have been occasional reports of Russian small arms falling into the hands of the Houthis. However, just like with Iran, this has reached another dimension in the past three years. Russia has reportedly helped the Houthis target ships in the Red Sea by sharing intelligence with the militia. In September 2024, Western media also reported that Moscow was considering the transfer of Yakhont anti-ship missiles to the Houthis (a weapon system that Russia already supplied to Lebanese Hezbollah). Such arms transfers would qualitatively increase the firepower of the Houthis and raise the vulnerability of commercial ships crossing the Red Sea, which the Houthis have targeted since the Gaza war started in October 2023. According to several reports, the connections between the IRGC and the Houthis have facilitated this Russia-Houthi cooperation.

Again, Gulf decision makers might assess that this development does not threaten them directly as they stay largely away from the Red Sea crisis. Gulf states distanced themselves from Israel and the Western navies that launched naval operations against the Houthis. Apart from Bahrain, they declined to participate in the U.S.-led Prosperity Guardian operation and refused to host the headquarters of the European Union operation Aspides. As a result, Gulf ships and assets have not found themselves in the line of fire. However, the Houthis’ engagement with Russia provides them with capabilities and military know-how that matters beyond the Red Sea crisis.

Before the Gaza war, Gulf states had concluded that they had to live with a Yemen that included the Houthis. This was already a shaky process because the Houthis displayed no intention of sharing power with the Saudi-backed or Emirati-backed factions inside Yemen. However, the predicament is now even bigger.

In the past two years, the Houthis have grown stronger, as they learned to work and fight not only with Iran but also with a major power like Russia. In fact, after the conflicts in Gaza and Lebanon, the Houthis may be the most prominent nonstate actor left in the Middle East. Contrary to Hamas and Hezbollah, the Houthis in Yemen border the Gulf Cooperation Council states and will shape their security environment for the near future.

Altogether, Russia’s strategy toward the Houthis and Iran might have been driven by its conflict with the West. Moscow needed partners like Iran and North Korea to help strengthen its war effort. Supporting the Houthis also enabled Russia to drag Western navies into lengthy and costly operations in the Red Sea. But even if the Ukraine war comes to an end, the implications of these Russian partnerships with Iran and the Houthis will last, and the consequences will be felt, first and foremost, in the Gulf. While the Gulf states’ diplomacy of multialignment on the Ukraine war might have succeeded, it won’t help in tackling the new security challenges enabled by Russia in their neighborhood.