New allegations about Iranian support for Yemen’s Houthis have emerged in media reports and official comments, highlighting the opaque nature of the alliance.

Media outlets have reported that Iran’s Islamic Revolutionary Guard Corps (IRGC) aided the Houthis as they seized swaths of western Yemen and launched their most potent and sophisticated attacks yet on Saudi Arabia, which supports the internationally recognised Yemeni government fighting the Houthis.

Iranian support for the Houthis reported by the media includes training, intelligence, tactical guidance and help in targeting for drone and missile attacks.

If true, this will undoubtedly escalate tensions between Iran and Saudi Arabia, given that the kingdom has been targeted by dozens of Houthi drones and missiles in recent weeks, including an attack on King Khalid International Airport in Riyadh that killed 13 people. Saudi energy facilities and oil tankers have also been targeted by the group.

Iranian backing, according to the reports, contributed to a September offensive by the Houthis, an armed group also known as Ansar Allah (Arabic for Supporters of God). Those battles saw the Houthis win control of Yemen’s Red Sea coastline and the strategically important Bab al-Mandeb strait.

The Wall Street Journal reported that Iranian Mahan Air flights ferried IRGC paramilitary officers, drone parts, missile guidance systems and impact detonators to the Houthis in Yemen. IRGC officers were also reportedly on the front lines directing Houthi attacks.

The spokesperson for the Saudi-led coalition supporting Yemen’s government, Major-General Turki al-Maliki, confirmed the presence of an external state actor behind the Houthis’ evolving arsenal but did not mention the state in question.

Al-Maliki noted that the Houthis, who have been at war with the government since 2014, have acquired advanced technologies with regional assistance.

This support has made the Houthis the first nonstate armed group to deploy ballistic missiles, offensive and suicide drones, and explosive-laden, high-speed boats, he said, although other Iranian allies, such as Hezbollah and Iranian militias, also possess such weaponry.

While the Houthis have stressed their independence from Iran, the two groups are ideologically aligned. They have also been accused of collaborating closely on military matters, evident in the Houthis’ missile arsenal.

Analysts who spoke to Al Jazeera all agreed that the “regional assistance” the Houthis are receiving points towards the IRGC although Iran and the Houthis denied this.

One indication of this is the bombing of Sanaa International Airport in July before an Iranian plane carrying a Houthi delegation travelling from Tehran was due to land. The Yemeni government, which said its forces carried out the attack, accused “the Iranian aircraft” of violating Yemeni airspace.

“[Recent reports] confirm what is known to experts for years as the Revolutionary Guard and Hezbollah experts engaged in managing the operational planning of battles against the Yemeni government and neighbouring countries, including the Kingdom of Saudi Arabia,” Ibrahim Jalal, a Yemen-focused analyst, told Al Jazeera.

“For example, the killing of Hassan Irloo, the Revolutionary Guard envoy to the Houthis, in Yemen after the military campaign on Marib in 2021 is one of the important indicators, in addition to Mahan aviation flights that transported more experts ahead of the Houthis’ internal and external escalation during July of this year.”Ali al-Dahab, a military and strategic security affairs expert, agreed that the advanced weaponry used by the Houthis indicates an Iranian role in recent operations.

“What was leaked about Iranian support for the Houthis through this report did not add anything new except that it confirmed the confirmed, and what it added perhaps is that weapons smuggling, especially precision technologies for missiles and unmanned aircraft, takes place via small submarines,” al-Dahab told Al Jazeera.

“This issue is not everything being smuggled from Iran to the Houthis because there are interceptions of smuggled shipments revealed by the joint forces that were controlling the Mocha coast to Bab al-Mandeb before the Houthis’ control and before its break in September.”Al-Dahab pointed out that while smugglers historically have used dhows, traditional wooden sailboats, to mislead naval coalitions, employing submarines is a new method used by the Houthis, akin to the tactics used by organised criminal groups in the Americas.

“It indicates that Iran focuses on the Houthis as the centre of military and security gravity south of the Red Sea and, therefore, provides them with these weapons, ammunition, expertise and information in anticipation of a battle that may break out in the Strait of Hormuz,” al-Dahab said. “Therefore, the Houthis play a supporting role for them in the Bab al-Mandeb strait.”He warned of broader implications for international shipping with the Houthis now in control of Bab al-Mandeb, a narrow waterway linking the Gulf of Aden and the Red Sea.

“The greatest danger now is that substate entities in the southern Red Sea and Gulf of Aden region unite under Iran’s leadership to confront the United States, Britain and Europe in general if a battle breaks out in the Gulf of Aden and the strait,” al-Dahab said.

Saudi Arabia and Iran had appeared to have patched up years of hostilities, including the suspension of diplomatic relations, with a China-brokered reconciliation agreement signed in Beijing in 2023.

Hesham Alghannam, a Riyadh-based fellow at the Carnegie Endowment for International Peace, said he doubts whether Saudi Arabia ever read the Beijing agreement as reconciliation but as a way of lowering tensions. Differences on geopolitical issues have continued between the two countries since the agreement was signed, including on Yemen, which lies on Saudi Arabia’s southern border.

“That isn’t a breach you can take to a lawyer. It’s keeping two files apart, and it works until someone says it out loud. That’s what’s changed,” Alghannam told Al Jazeera.

“Honestly, the deeper question was never whether Tehran signs [the agreement with Saudi Arabia]. It’s whether anything Tehran signs reaches the people holding the launchers,” he added, referring to Iran-aligned armed groups, such as the Houthis.

“We know how the other sequence ends. In 2014, the [Houthis] were offered seats, special status for Saada [the northern Yemeni stronghold of the Houthis] and a share of the executive authority in Yemen in return for handing the heavy weapons to the state,” he added.

What followed was the Houthis seizure of the capital, Sanaa, in September 2014, forcing the government to flee south, and the later killing of former President Ali Abdullah Saleh.

“What followed was the seizure of the institutions, the president detained, parliament dissolved. The gains were banked, and the guns were kept,” Alghannam added.

“Saleh partnered with them, and he was killed in the street in 2017. Even after taking Sanaa, they didn’t become the state. They built a network of supervisors sitting over every official post. So the Saudi red line is one thing, no armed group or second army inside one state.”The Saudi-led intervention in Yemen began in March 2015 and led to another direct conflict between Riyadh and the Houthis. Despite the massive support Saudi Arabia provided the internationally recognised government, it failed to retake Sanaa. This highlighted weaknesses within the anti-Houthi coalition, including divisions between the internationally recognised government and southern separatists.

“The lesson of 2015 wasn’t that acting firmly leads to a long war. It was that announcing a goal earlier than you should [do] does because once it’s said out loud, you’re bound to it long before you can deliver it,” he said.

“What Riyadh is trying to do now is easy to say and hard to do, but it’s crucial: tie the money and the weapons to real integration under one command, not to declared loyalty.”Hassan Ahmadian, an assistant professor of political science at the University of Tehran, told Al Jazeera that Iran seeks technological independence for partners rather than perpetual reliance.

“This pattern is not like the United States pattern, which keeps whoever follows and allies with it in need of it, meaning [they have] to buy from the United States the weapons he needs, and the main weapon is basically not given to him if it is an Arab or Islamic country specifically,” he said.

“As for Iran, the ally is provided with the technology to create and produce the weapon, and this is not only in Yemen but in other regions and even in Gaza as much as possible where the technology was transferred because the view is different.”Ahmadian said enabling Iran’s allies to produce their own weapons is a strategic move by Tehran and the Houthis are also motivated by breaking the Saudi siege on territories it controls in Yemen.

“The view is that this technology helps in confronting a common enemy, and therefore, strengthening this capability independently of Iran is in itself a strategic interest for Iran,” Ahmadian said.

“Notice that there is an advance for Ansar Allah [the Houthis] linked to the justice of the cause as there is a siege imposed on the Yemenis affecting 70 percent to 80 percent of the society controlled by Ansar Allah and the Sanaa government. So this cause, breaking the siege, is a just cause. … The regional circumstance gave [the Houthis] a motive that this is the time to pressure Saudi Arabia to break the siege, and this is what actually happened.”