Post-12-Day War, Iran Continues To Invest in the Houthis

Tehran is still arming the Houthis. Yemen’s National Resistance Forces (NRF), an anti-Houthi coalition, intercepted 750 tons of Iranian weapons en route to the Houthi-controlled port of al-Salif from Djibouti on June 27. Though the Islamic Republic of Iran has increasingly diversified shipping routes to mask its arms proliferation into trade between the Horn of Africa and the Arabian Peninsula, the latest interdiction is one of the most significant considering the past decade of Iranian material support to the Yemeni terror group.

That Tehran is intent on rearming its Axis of Resistance, a transnational network of terror proxies, following the costs imposed on it during the 12-Day War with Israel and the United States, is another sign of the importance of this Axis to both the regime’s strategy and revolutionary ideology. “The interdiction of this massive Iranian shipment shows that Iran remains the most destabilizing actor in the region,” said General Michael Kurilla, commander of U.S. Central Command (CENTCOM), on July 16.

Iran Remains the Houthis’ Most Important Foreign Backer

In a February letter to the UN Security Council, the Islamic Republic rejected the notion that it was in “violation of arms embargoes” and that it was “fueling the conflict in Yemen.” UN Security Council Resolution 2624, passed in 2022, has an open-ended international arms embargo on the Houthis that expands an earlier resolution from 2015 containing an arms embargo against Yemeni and Houthi political leaders.

However, a decade of Iranian weapons proliferation tells a different story. Since the Houthi capture of Sanaa in 2014 catapulted the group into a member of Iran’s Axis of Resistance, the United States and international partners had intercepted at least 20 separate weapons shipments from Iran as of January 2024, according to the Defense Intelligence Agency (DIA). Iran’s evolving relationship with the Houthis has resulted in the Houthis’ possession of more advanced weapons than any other member in its Axis, despite their being the newest.

Iranian Arms Shipments Prove Why the Houthis Are Its Most Potent Proxy

CENTCOM said many of the systems in the recent NRF seizure “were manufactured by a company affiliated with the Iranian Ministry of Defense that is sanctioned by the United States.” This shipment included land-attack cruise missile (LACM) turbo-jet engines used in Iran’s Paveh-class LACM, which the Houthis call the Quds LACM; electro-optical seekers for anti-ship ballistic missiles (ABMs); an entire one-way attack drone (the Shahed-107) and dozens of piston engines; anti-tank guided missile (ATGM) warheads; man-portable air defense systems (MANPADs); anti-ship cruise missiles (ASCMs) such as the Ghadir (Iranian C-802) and the newer Sejil; and a counter-drone missile unveiled by Iran in February dubbed the Qaem-118.

Smaller interceptions in 2024 and 2025 have highlighted the Houthis’ use of commercially available components to produce systems domestically, especially drones. However, this seizure of Iranian weapons and components demonstrates that the key elements of the Houthis’ supply chain remain reliant on Tehran.

U.S. Needs an Updated Counter-Houthi Strategy Post-Strikes

Despite separate but substantial air campaigns by the United States and Israel against the Houthis this year, Houthi maritime and missile attacks persist, necessitating an updated strategy. This should include efforts to financially isolate the Houthis. Trump administration sanctions identified hundreds of millionsof dollars that the Houthis have moved through exchange houses, crypto wallets, and financial institutions. Washington should closely scrutinize any financial institutions continuing to operate out of Sanaa for potential sanctions violations. It should also make the case to internationalize sanctions against Houthi financiers that the U.S. Treasury has already sanctioned and identified.

Washington should not shy away from leading a more comprehensive, maritime weapons interdiction effort to impede Iran’s resupply efforts. Simultaneously, it should empower Yemeni naval and coast guard forces that have helped to make this interdiction possible. Finally, the Trump administration should consider pairing this increased interdiction capacity with strikes against the Houthi arsenal and political leaders to deter more attacks on commercial shipping and to strain Iran’s re-arming efforts. Washington cannot allow Tehran to continue proliferating weapons to its regional terror network as a low-cost, low-risk way of sustaining its shadow war against the United States and Israel.

Bridget Toomey is a research analyst at the Foundation for Defense of Democracies (FDD), where Behnam Ben Taleblu is the senior director of the Iran Program. For more analysis from the authors and FDD, please subscribe HERE. Follow Bridget and Behnam on X @BridgetKToomey and @therealBehnamBT. Follow FDD on X @FDD and @FDD_Iran. FDD is a Washington, DC-based, nonpartisan research institute focusing on foreign policy and national security.