The Yemeni militant group is poised to disrupt another key chokepoint in the global energy supply.

Missiles could soon be flying over the Red Sea again. On Monday, Yemen’s Houthis declared a maritime blockade of Saudi Arabia, which threatens vital oil shipped from the kingdom’s port of Yanbu. If the terrorist group carries out its threats, it is likely to open another front in the conflict between the United States and Iran and its proxies.

Blockades have been an effective tactic used by the group’s sponsors in Tehran. The Islamic Republic’s ability to close off the Strait of Hormuz at will has been one of its most effective tools to pressure the Trump administration into negotiations. More than 20 percent of the world’s oil transits the chokepoint at the entrance to the Persian Gulf. In the recent memorandum of understanding intended to halt the war between Iran and the United States, US negotiators came ready to make significant concessions.

Now, Iran’s Yemeni proxy is executing a similar playbook. They are threatening the strategic maritime passageway leading to the Red Sea from the Indian Ocean—the Bab El-Mandeb Strait—on behalf of their patrons in Tehran. But by enacting a limited blockade focused on Saudi Arabia, they hope to concentrate pressure on the kingdom that leads the anti-Houthi coalition. The Houthis are a Yemeni terror group that controls much of the country, and the maritime blockade against Saudi Arabia is also the latest blow to the fragile truce that has governed relations between the two since early 2022.

Just days before the Houthis declared the blockade, Iranian sources told Reuters that the Yemeni group had been instructed to close the Red Sea if President Donald Trump followed through on a threat to strike Iran’s power grid, which Iranian officials claim he did on July 17. Abdul-Malik al-Houthi, the leader of the eponymous group, didn’t comment on this threat in his speech immediately after the reports emerged. Instead, he focused on Saudi Arabia. However, a blockade of the kingdom would achieve much of Iran’s desired impact.

Saudi Arabia has rerouted its oil exports, which usually transit the Persian Gulf, to the Red Sea. Using the pipeline that moves oil extracted in the country’s Eastern Province to the west coast, Riyadh exports about 4 million barrels per day (bpd) via its Red Sea port of Yanbu.

Oil exported from Yanbu then moves south, past Houthi-controlled territory and through the Bab El-Mandeb chokepoint to buyers in Asia. In June, maritime intelligence firm Kpler reported petroleum exports through Bab El-Mandeb amounted to 7 percent of global oil output at 7.4 million bpd. In 2025, 4.2 million bpd transited Bab El-Mandeb.

The Houthis could choose to enforce the blockade by targeting Yanbu with drones and missiles.  After the Houthis seized the Yemeni capital of Sanaa in 2014, Saudi Arabia led a coalition to fight the group. The Houthis then undertook cross-border attacks on the kingdom’s infrastructure. In 2022, the Iran-backed group targeted a refinery in the port of Yanbu, causing a temporary reduction in output.

In September 2025, as part of the Houthi campaign against Israel during the war in Gaza, the group launched a missile at an Israeli-owned ship 40 nautical miles from Yanbu, much further north than their usual area of operations. While this attack didn’t target Saudi Arabia, it sent an unmistakable message about the group’s capability to do so.

Alternatively, the group could focus on ships traveling to or from Saudi ports as they approach Bab El-Mandeb, which lies very near their territory. The closer range would enable them to use a wider range of munitions or to target vessels with fast-attack craft. Saudi energy exports would be stymied, with the majority loaded on very large crude carriers (VLCCs) bound for Asia. Any alternative path, including rerouting around Africa, is both expensive and time-consuming.

So far, the Houthis have only issued statements enacting the blockade—including the initial announcement and a subsequent email to shippers not to call at Saudi ports; they have not yet targeted Saudi ports or vessels to implement it. However, within 48 hours of the Houthi announcement, five vessels—four inside the Red Sea and one in the Gulf of Aden—turned around to avoid crossing Bab El-Mandeb, according to maritime intelligence firm Windward.

The Houthis have also been engaged in a months-long campaign to establish a new normal between the group and Saudi Arabia. The effort has included striking inside the kingdom. As recently as last week, the Yemeni group launched drones and missiles at Abha International Airport in southern Saudi Arabia. That followed a Saudi attack on Houthi-controlled Sanaa International Airport to prevent an Iranian flight from landing.

Saudi Arabia, on behalf of the internationally recognized government of Yemen, maintains an air blockade of Houthi territory which permits select flights but has denied direct Iranian access for roughly a decade to prevent Tehran from arming and supporting its proxy.

To forestall domestic discontent with yet another conflict, the Houthis are framing this escalation as “a siege for a siege.” This narrative portrays the group as defenders of Yemeni rights and economic opportunities. Instead of attempting to convince already suffering Yemenis to weather another conflict, this time on behalf of Tehran, the Houthis have recast themselves and the conflict under a nationalist banner.

In the months preceding this escalation, the Houthis increasingly called for Saudi Arabia to reimburse the group for damage incurred by the Saudi-led campaign in the Yemeni civil war, including lost revenue and unpaid public-sector salaries. In March, Abdul-Malik claimed more than $57 billion in losses in the oil sector due to the conflict.

The Houthis’ ostensible target is their neighbor to the north. Still, it’s no coincidence that the terrorist group’s blockade increases the leverage that Iran—as the Houthis’ patron—holds over the global oil market.

The United States has largely ignored the Houthis since Operation Rough Rider, the March to May 2025 air campaign during which US forces struck more than 1,000 Houthi targets, and the ensuing ceasefire between the two sides. But Washington cannot ignore further threats to the already constrained Middle East energy corridors.

While Trump likely isn’t eager to open another front in the US-Iran conflict, he should refrain from hamstringing Gulf state efforts to counter the Houthis. Iran cannot be permitted to protect a second proxy in deals with the United States, as the regime did with Hezbollah by including Lebanon in the memorandum of understanding.

Until the Houthis are uprooted from their enclave along the Red Sea, or denied access to Iranian-supplied weapons, their threat will loom over Saudi Arabia and the global community.

About the Author: Bridget Toomey

Bridget Toomey is a research analyst at the Foundation for Defense of Democracies (FDD), focusing on Iranian proxies, specifically Iraqi militias and the Houthis. Before joining FDD, she was a Fulbright fellow in Israel, where she completed an MA in security and diplomacy at Tel Aviv University. During her undergraduate studies, she interned for the American Enterprise Institute’s Critical Threats Project, focusing on jihadi terror groups, and for the Senate Foreign Relations Committee. She holds a BA in government with a minor in modern Middle Eastern studies from Harvard University.

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