The Houthis, which belong to the Zaidi branch of Shiite Islam, are an Iranian-backed and armed religious and political movement in Yemen. The Houthis waged a series of bloody insurgencies against the Yemeni government for over a decade, leading to that regime’s overthrow in 2015. The movement is known for its virulently anti-American and anti-Semitic rhetoric, including the group’s motto: “God is great! Death to America! Death to Israel! Curse upon the Jews! Victory to Islam!”
Beginning in 2004, the Houthi rebels waged a low-level insurgency against the Sunni-dominated, internationally recognized Yemeni central government, a key U.S. counterterrorism ally. Iran and Hezbollah offered limited assistance to the Houthis, whose ideology emulated Khomeinism. Since at least 2009 assistance came in the form of arms and training, with the Quds Force organizing crude Iranian small-arms shipments that were occasionally intercepted by Yemeni and U.S. naval patrols.
The Houthis made significant territorial gains in 2014 and 2015, including the capture of Yemen’s capital, Sanaa, in September 2014, resulting in the removal of President Abd-Rabbu Mansour Hadi from power. Qassem Soleimani, the former commander of the Islamic Revolutionary Guard Corps (IRGC) Quds Force, remarked that the fall of Sana’a represented a “golden opportunity” for Iran. An allied Shia force now controlled the capital of a neighboring country to Saudi Arabia, Iran’s primary Middle Eastern geostrategic adversary. In conjunction with Hezbollah, the Quds Force set about remaking the Houthis in Hezbollah’s image, building up their military capabilities, and dispatching senior Quds Force advisors to train them.
On October 2, 2015, the United Nations announced it would broker talks between the Houthis and the Yemeni government in Oman. At the time, government officials stated the Houthis were merely maneuvering tactically by showing their willingness to engage in talks. The Houthis have refused to relinquish territory they have occupied—a stipulation to end Yemen’s civil war under United Nations (U.N.) Security Council Resolution 2216.
Iran’s relationship with the Houthis plays into Iran’s strategy of controlling key Arab waterways. Control of Yemen and its strategic ports affords control of vital commercial and energy shipping lanes that connect the Red Sea to the Indian Ocean and the Middle East to Europe. Control of the Bab el-Mandeb Strait poses a strategic nuisance for Israel, enabling Iran to cut off its naval trade routes to Asia and opening up a new conduit for Iran to smuggle weapons to Hamas and other terrorist proxies. Iran has thus sought to gain a foothold in Yemen which would allow it, despite the weakness of its naval forces relative to others in the region, to sabotage international commerce and energy markets when its interests are threatened.
In December 2017, the Houthis assassinated former Yemeni president Ali Abdullah Saleh, their erstwhile enemy and then ally, after he turned against them again and proposed reconciliation with the Saudi-led anti-Houthi coalition. Iranian leaders and regime-affiliated media outlets celebrated Saleh’s killing and said the Houthis are inspired by Iran’s 1979 Islamic Revolution and similar to Iranian-supported militant groups in Syria, Iraq, and Lebanon.
Iran’s aid to its Houthi proxies has provided a low-risk, cost-effective avenue for it to increase its political and military influence in Yemen.
The Houthi movement’s organizational structure is unclear and likely continues to evolve. The movement began as a grassroots religious organization aimed at youth in the 1990s, but over time it has entered politics and developed military capabilities. Following the killing of movement founder Hussein Badr al-Din al-Houthi by Yemeni forces in 2004, the Houthis were led by Hussein’s father, spiritual leader Badr al-Din al-Houthi. The movement’s current leader is Hussein’s younger brother, Abdul Malik al-Houthi. In 2021, the U.S. Department of State sanctioned three of the Houthis leaders, Abdul Malik al-Houthi, Abd al-Khaliq Badr al-Din al-Houthi, and Abdullah Yahya al-Hakim as Specially Designated Global Terrorists. Likewise, the Houthi group was designated in its entirety as a Foreign Terrorist Organization and Specially Designated Global Terrorist. The Biden administration later revoked these designations, citing humanitarian considerations.
In 2020, Iran dispatched a new ambassador to the Houthis in Yemen, Hassan Eyrlou. Eyrlou is reportedly an IRGC Quds Force officer, whom the U.S. Department of the Treasury accused of supporting “the group’s operations throughout the Arabian Peninsula and Yemen” and also trained members of Hezbollah in Iran. Eyrlou’s arrival is a significant development, with some observers believing Tehran is trying to establish a similar ambassadorship to the one it holds in Iraq, with an IRGC officer embedded as a diplomat to run Iranian operations in the country.
Iranian Material and Financial Support of The Houthis' Violent Activities
Beginning in 2004, Shia Houthi rebels waged a low-level insurgency against the Sunni-dominated, internationally recognized Yemeni central government, a key U.S. counterterrorism ally. Iran and Hezbollah offered limited assistance to the Houthis, whose ideology emulated Khomeinism, since at least 2009 in the form of arms and training, with the Quds Force organizing crude Iranian small-arms shipments that were occasionally intercepted by Yemeni and U.S. naval patrols. The Quds Force had also provided guidance to the Houthis to set up an affiliated political party, Ansar Allah, mimicking the Hezbollah model of fusing militant and political power.
Yemeni officials have long accused Iran’s Shiite Islamist regime of providing political, financial, and logistical support to the Houthi rebels and other secessionist movements in Yemen. Despite a 2009 U.N. report confirming such claims, both Iran and the Houthis have denied engaging in past cooperation.
For instance, the Iranian ship Jihan I was seized in 2013, allegedly en route to Yemen with arms meant for the Houthis. The cache, as Reuters reported in December 2014, included “Katyusha rockets M-122, heat-seeking surface-to-air missiles, RPG-7s, Iranian-made night vision goggles and ‘artillery systems that track land and navy targets 40km away,’” as well as “silencers, 2.66 tonnes of RDX explosives, C-4 explosives, ammunition, bullets and electrical transistors.”
Subsequent reports confirmed Iranian support for the Houthis, including a Reuters article in December of 2014. One source stated, “We think there is cash, some of which is channeled via Hezbollah and sacks of cash arriving at the airport.” Only in 2015 did Iran finally acknowledge providing “direct support” to the Houthis.
The Houthis have historically trained their fighters in Yemen’s mountainous north. The Quds Force of Iran’s IRGC has trained Houthis in Yemen and Iranian military leadership is also believed to be present in Yemen to provide strategic military advice. In March 2015, Saudi foreign minister Adel al-Jubair also alleged that Hezbollah operatives were advising the Houthis. In the same month, Syrian military officials reportedly were in Yemen assisting the Houthis as well. In early 2015, U.S. officials reported that the IRGC’s training of Houthi rebels covered the use of advanced weapons, which the Houthis seized from Yemeni military bases.
The Houthi takeover of northern Yemen and subsequent overthrow of the Hadi government created an opportunity for Iran to establish a foothold as the dominant influence in Yemen, and it responded by escalating its material and advisory support to the Houthis. The Quds Force stepped up illicit arms exports of increasingly sophisticated weaponry, including Sayyad 2C surface-to-air missile, guided anti-ship missiles, Qiam-1 ballistic missiles, kamikaze aerial drones, landmines, Kalashnikov variant rifles, RPG-7 and RPG-7v rocket-propelled grenade launchers, machine guns, AK-47 assault rifles, precision rifles, and anti-tank missiles. In January 2019, the U.N.’s Panel of Experts on Yemen reported that they had “traced the supply to the Houthis of unmanned aerial vehicles and a mixing machine for rocket fuel and found that individuals and entities of Iranian origin have funded the purchase. The Quds Force’s support has helped the Houthis overcome some core deficiencies, including strategic planning, political mobilization, and operating advanced weaponry.
In addition to bolstering the Houthi forces, the Quds Force has also reportedly mobilized elements of its foreign legion of proxy militias, injecting Shia mercenary forces into the Yemen conflict, mirroring its strategy in Syria. According to a March 2017 Reuters report, “Iranian and regional sources said Tehran was providing Afghan and Shi‘ite Arab specialists to train Houthi units and act as logistical advisers. These included Afghans who had fought in Syria under Qods Force commanders.”
In March 2017, former Quds Force commander Qassem Soleimani reportedly convened a meeting of senior IRGC military officials to explore ways to further “empower” the Houthis. An official at the meeting noted that “Yemen is where the real proxy war is going on and winning the battle in Yemen will help define the balance of power in the Middle East.” Since that time, Iran has introduced increasingly complex weaponry into the Yemeni theater, and the Houthis have stepped up their aggression in accordance with Iranian foreign policy objectives.
Missile and Drone Attacks on Saudi Arabia
In a similar vein to Iran’s efforts to establish forward operating bases in Syria and Lebanon from which to encircle, threaten, and provoke Israel, Iran’s relationship with the Houthi rebels in Yemen offers Iran a staging ground to attack another key U.S. ally and Iranian adversary, Saudi Arabia.
Since 2015, the Houthis have used Yemeni territory under their control as launching pads to fire more than 100 missiles and drones at Iranian rival Saudi Arabia. Such strikes have landed on multiple cities, including Riyadh, the Saudi capital. Targeted locations include the king’s official residence, military bases and encampments, oil refineries, the Riyadh international airport, and shopping malls. Further, as the Congressional Research Service notes, “Since 2016, the Houthis have periodically targeted commercial and military vessels transiting and patrolling the Red Sea using naval mines, rocket-propelled grenade launchers, anti-ship missiles, and waterborne improvised explosive devices (WBIEDs). Some of the weapons used reportedly have been supplied by Iran, including sea-skimming coastal defense cruise missiles.”
Evidence indicates that Iran is arming and, in some cases, directing the Houthis in their missile campaign, contrary to Tehran’s denials and in violation of an arms embargo imposed by the United Nations Security Council in April 2015. An independent U.N. monitoring panel stated in November 2017 that remnants from four ballistic missiles fired by the Houthis into Saudi Arabia likely came from the Iranian-made and designed Qiam-1 missile. In December 2017, U.S. Ambassador to the U.N. Nikki Haley and Pentagon officials displayed debris from missiles fired into Saudi Arabia, claiming that the markings on and designs of the missiles demonstrated that they were made by Iran. The U.N.’s finding of Iranian origins in the Houthis’ missiles continued well into 2018, with panel after panel affirming the Iranian connection. One U.N. report from January 2018 found that recently inspected missiles and drones “show characteristics similar to weapons systems known to be produced in the Islamic Republic of Iran,” and, therefore, the panel “continues to believe” that Tehran is giving missiles and other arms to the Houthis.
Drones have also played a significant role in the Houthis efforts to sow terror against coalition targets both inside Yemen and within Saudi Arabia and the UAE. In March 2019, U.S. CENTCOM Commander Joseph Votel testified before the House Armed Services Committee, “The ballistic missile threat and armed UASs (Unmanned Aerial Systems) emanating from Yemeni territory continue to pose a significant risk, as the Houthi’s consider civil infrastructure as legitimate military targets.” The group’s frequent usage of UAVs and demonstration of long-range drone suicide attack capabilities places them in league with Hezbollah as among the world’s most active and sophisticated non-state actors in the drone space.
In May 2018, the U.S. Treasury Department sanctioned five Iranian individuals affiliated with the IRGC and its Quds Force for their role providing ballistic missiles and related technical expertise to the Houthis.
Iran has recently bragged openly about their support for the Houthis, with an IRGC general telling IRGC-controlled media that the Guards had instructed the Houthis to attack two Saudi oil tankers in July 2018.
Iran reportedly also continues to provide other forms of arms to the Houthis. For example, an independent watchdog organization claimed in March 2018 that roadside bombs found in Yemen resemble ones used by Iranian proxies in Lebanon, Iraq, and Bahrain.
Beginning in April 2019, following the U.S. State Department’s designation of the IRGC as a foreign terrorist organization, Iran initiated a campaign of escalating its malign activities and regional aggression. As a key Iranian proxy, the Houthis are heavily engaged in this campaign and have escalated their missile and drone attacks on Saudi energy infrastructure, airports, and military sites to unprecedented levels.
On May 14, 2019, unmanned aircraft systems targeted two pumping stations on the East-West pipeline carrying crude oil from Dhahran to Yanbu. Yemen-based Iran-backed Houthi militants claimed responsibility. On June 12, 2019 Saudi-led coalition senior officials reported a cross-border cruise missiles attack at Abha International Airport, injuring 26 civilians. Yemen-based Iran-backed Houthi militants claimed responsibility for this attack. On August 17, 2019 Yemen’s Iran-backed Houthi militants struck a natural gas liquids plant at Shaybah oilfield in the Kingdom’s Empty Quarter with drones. The drone strike damaged the facility and caused a fire. No deaths or casualties were reported.
On January 29, 2020, the Iran-backed Houthi’s said it had fired rocket and drone strikes at Saudi targets including Aramco oil facilities.
On March 18, 2020, the Saudi-led Arab coalition intercepted and destroyed two explosive-laden boats that were launched by the Iranian-backed Houthi's from Yemen's Hodeidah province.
On June 23, 2020, Saudi Arabia announced that Houthi rebels had launched a simultaneous ballistic missile and explosives-laden drone attack on various targets throughout the Kingdom, including on the cities of Najran and Jizan. Saudi Arabia reportedly intercepted three missiles and eight drones, but it was unclear whether any drones made it to their targets. A coalition spokesman accused the Houthis of targeting civilians in the attack. The incident underscored the danger posed by simultaneous missile and drone barrages, a tactic the Houthis have apparently mastered and which can potentially overwhelm air defense systems.
On November 12, 2020, Saudi Arabia reportedly thwarted an attempted Houthi attack against an oil products terminal in the port city of Jizan. The Houthis used unmanned boats laden with explosives in the attempted attack, which Saudi forces intercepted and destroyed, but which still caused a small fire at the facility. The Saudi energy ministry released a statement on the attempted attack, declaring “The Kingdom of Saudi Arabia strongly condemns the cowardly attack, adding that such criminal acts directed against vital facilities do not target the Kingdom alone, but they also target the security of oil exports, the stability of energy supplies to the world, the freedom of international trade, and the entire global economy.”
In 2021, after the Biden administration’s rescission of the Foreign Terrorist Organization and Specially Designated Global Terrorist designations of the Houthis, the Houthis became more empowered on the ground in Yemen. They renewed an offensive to retake Marib, as well as engaged in repeated ballistic missile and drone-related attacks on civilian areas in Saudi Arabia as well as Aramco energy infrastructure. But at the same time, while the Houthis have claimed responsibility for targeting installations like the Ras Tanura port on March 7, there is evidence that some of these attacks may be originating from Iraq, with the Houthis covering for Iran’s proxy network there, by claiming they carried out the operation. An advisor to the Saudi royal court told the Wall Street Journal that “[a]ll indications point to Iran.” He said it wasn’t clear whether the origin for the March 7 attack was Iraq or Iran, but that it hadn’t come from the direction of Yemen.
This comes as the Biden administration held their first direct meeting with the Houthis on February 26, 2021. With the Houthi leadership divided, these attacks on Saudi Arabia could be indicative of an internal struggle over strategy.
Hezbollah’s Assistance to the Houthis
The Iranian proxy group Hezbollah, a terrorist organization operating in Lebanon and elsewhere, also has longstanding ties to the Houthis, who are fellow Shiites. Working with Iran, Hezbollah reportedly operates on the ground in Yemen, arming, training, and even fighting for the Houthis. Analysts have speculated that the Houthis seek to replicate in Yemen Hezbollah’s Lebanese model of a “state within a state.”
Hezbollah operatives themselves have reportedly admitted that the group has a ground presence in Yemen and fights directly against the Saudi-led coalition. A Hezbollah commander told the Financial Times that the group began training with the Houthis in 2005. “They trained with us in Iran, then we trained them here and in Yemen,” he said. A Hezbollah commander reportedly told researchers in 2016, “After we are done with Syria, we will start with Yemen, Hezbollah is already there. Who do you think fires Tochka missiles into Saudi Arabia? It’s not the Houthis in their sandals, it’s us.” A Houthi militia leader confessed after surrendering to coalition forces in 2017 that Iran and Hezbollah operatives were operating covert training facilities in Yemen.
Coalition and United Nations officials have also claimed that Hezbollah is aiding the Houthis. Yemeni President Abd-Rabbu Mansour Hadi claimed in 2016 that Hezbollah Secretary-General Hassan Nasrallah wrote to him that “Our fighters arrived in Yemen to teach the Yemeni people the essence of governing.” In June 2018, the anti-Houthi coalition stated that coalition forces had killed eight Hezbollah members in Yemen. That August, Khalid bin Salman, the Saudi ambassador to the U.S., said that not enough attention was paid to “not only the direct assistance the Al Houthi militia receives from the Iranian regime, but also the existence of Hezbollah commanders on the ground.” He added that a coalition raid on a Houthi site had “revealed a Hezbollah operative training, advising [the Houthis] on asymmetric warfare, and showed background portrait [sic] of Iran’s ‘Supreme Leader’ on militia’s computer [sic].” Ambassador bin Salman also tweeted evidence of ties between the two groups, including footage of a “Hizballah operative in Yemen advising the Houthis to use deception tactics such as using water tanks to store weapons, and smuggling fighters through civilian vehicles; endangering the lives of Yemeni civilians.” Saudi Foreign Minister Adel al-Jubeir has repeatedly accused Iran and Hezbollah of being responsible for missile attacks targeting Saudi territory. In July 2018, a coalition spokesman said “Hezbollah is the Houthis’ greatest arms supplier” and said the coalition had evidence that Hezbollah experts were on the ground in Yemen, training the Houthis and giving them a military communications system. And in October 2018, U.N. Secretary-General Antonio Guterres condemned Hezbollah’s involvement in Yemen.
In 2018, Nasrallah stepped up his group’s public support for the Houthis. On June 29, 2018, Nasrallah paid tribute to the Houthis in a public speech, even saying, “I wish I could be one of your fighters and fight under the guidance of your brave and dear leaders.” In mid-August, Hezbollah used its annual commemoration of its 2006 war against Israel to display pro-Houthis propaganda—namely, as the National reported, “a reconstruction of a bus hit by a Coalition airstrike which had killed a number of civilians and children in Saada province several days earlier that the Arab-led force later said had been a mistake. Organizers used the bus for journalists to photograph, complete with actors impersonating the victims, special effects smoke, red lighting and fake blood in an evocative image of the war.” And on August 19, 2018, Hezbollah disclosed that Nasrallah had met recently with a Houthi delegation in Beirut.
Houthi leader Abdul-Malik al-Houthi has reciprocated, praising Iran and thanking Nasrallah for his “solidarity.” He also promised that Houthis would fight alongside Hezbollah or Palestinian militants in a future war against Israel.
In late 2018 and 2019, the Houthis self-reported that they had fundraised roughly $500,000 for Lebanese Hezbollah after the group called for donations to offset the effects of U.S. sanctions. In a statement, the Houthi radio station said the funds would “support, aid and assist the resistance in Lebanon." The Houthis defended their provenance of funds to Hezbollah despite widespread poverty, hunger, and disease in Yemen, stating, “This is what Yemeni donors prefer of their own will, despite the siege and the cutting-off of their salaries.” Critics of the Houthis allege, however, that the group has diverted donations thought to be for the local war effort and used pilfered funds from excessive taxation of populations under its control. The diversion of funds away from Yemen, suffering under humanitarian crisis, to Lebanon demonstrates the subservience of the Houthis to Iran’s hegemonic regional project and underscores the group’s lack of concern for the welfare of its own subject population.
Designation As Terrorist Organization and Rewards for Justice
In 2014, Saudi Arabia and the United Arab Emirates designated the Houthis as a terrorist organization. In July 2019, the Arab Parliament, the Arab League’s legislative body, designated the Houthi movement as a terrorist organization and called upon the United Nations to follow suit. In 2021, the United States designated the Houthis as both a Foreign Terrorist Organization and a Specially Designated Global Terrorist. The Biden administration, however, has reversed these designations, while maintaining sanctions on Houthi leadership under Executive Order 13611.
In December 2019, the U.S. State Department designated Yemen's Houthi movement as an "Entity of Particular Concern" for violations against religious freedom based on recommendations by the U.S. Commission on International Religious Freedom (USCIRF). The USCIRF had previously raised alarms over acts of persecution by the Houthis against Yemen’s Bahai minority, blaming Iran for exporting religious intolerance to the Houthis. The designation would open the door for the U.S. to impose human rights sanctions targeting the Houthis and its leadership.
Likewise, in December 2019, the U.S. State Department offered a $15 million reward for information leading to Abdul Reza Shahlai, an IRGC Quds Force operative based in Yemen. U.S. Special Representative for Iran Brian Hook said: “[w]e remain gravely concerned by his presence in Yemen and potential role in providing advanced weaponry of the kind that we have interdicted to the Houthis.” The next month, in January 2020, the Trump administration attempted to strike Shahlai, given his destabilizing role in Yemen. Reports indicate this mission was unsuccessful.