Iran’s second front: Is the war in Yemen about to reignite?

YEMEN

As the Houthis threaten Saudi oil facilities and prepare to choke a second vital shipping route, a four-year truce risks giving way to renewed war in Yemen.

A FOUR-year truce between Saudi Arabia and Yemen’s Houthi movement is beginning to fracture, threatening to open a dangerous new front in the Middle East crisis.

The rupture came on Monday, when aircraft struck the runway at Sanaa International Airport to prevent an Iranian passenger plane carrying a Houthi delegation from landing in the rebel-controlled capital.

The Houthis blamed Saudi Arabia and retaliated by launching missiles and drones at Abha International Airport, near the Yemeni border.

Saudi air defences intercepted the attack, but the exchange marked the first claimed Houthi strike against the kingdom since an informal truce took effect in 2022.

Now the danger extends far beyond Yemen.

Iran has reportedly instructed the Houthis to prepare to close the Bab el-Mandeb Strait if the US attacks Iranian power infrastructure.

Missiles and drones are said to have been positioned near the entrance to the Red Sea, awaiting orders to target shipping.

With the Strait of Hormuz already severely disrupted by renewed fighting between Washington and Tehran, Houthi action could threaten both of the Middle East’s main maritime energy routes simultaneously.

But Owen Williams, Middle East and North Africa analyst at Sibylline, warns against viewing the Houthis simply as an Iranian proxy.

“We shouldn’t overstate the control that Iran has over the Houthis,” he says.

“Iran backs them and provides them with weapons, but they are also autonomous and will act in their own interests.

“If Iran was going to use the Houthis to create more disruption now, the more prudent use of their capacity would be to close Bab el-Mandeb or attack US-affiliated vessels in the Red Sea.

“Trying to start a war with Saudi Arabia would not end particularly well.”

The latest escalation began with an attempt by Iran’s Mahan Air to return a Houthi delegation from Tehran.

Yemen’s internationally recognised government refused permission for the flight to enter its airspace, but the aircraft continued towards Sanaa.

When efforts to turn it back failed, the runway was struck. The aircraft subsequently diverted to Hodeidah, another Houthi-controlled city on Yemen’s Red Sea coast.

Although the Yemeni government claimed responsibility, its forces lack a credible combat-air capability. Sibylline assesses that Saudi or Saudi-led coalition aircraft probably carried out the operation on its behalf.

The incident represented more than a dispute over an unauthorised flight.

Direct air links between Tehran and Houthi-held territory would help normalise Iran’s relationship with the group while challenging restrictions intended to prevent weapons and military equipment entering Yemen.

Pro-government forces have also stepped up attempts to interrupt Houthi supply lines.

This week the Southern Giants Brigades intercepted a vessel in Bab el-Mandeb allegedly carrying weapons-manufacturing equipment to Hodeidah.

For Riyadh, however, stopping the flight may have reopened a conflict it has spent years trying to escape.

Saudi Arabia intervened in Yemen in 2015 after the Houthis seized Sanaa and forced the government south.

What was intended as a rapid intervention developed into a costly and inconclusive war, accompanied by one of the world’s gravest humanitarian crises.

The UN-brokered truce formally expired in October 2022 but largely ended direct exchanges between Saudi Arabia and the Houthis.

That relative calm endured even as the group attacked commercial shipping during the Israel-Gaza war.

Williams does not expect a sudden return to full-scale warfare. Instead, he warns of “a slow progression towards a return to more normalised conflict”.

The balance within Yemen has shifted.

The UAE-backed Southern Transitional Council, which sought an independent southern Yemen, has lost much of its governing and military capacity. That has allowed the Presidential Leadership Council to begin consolidating previously fragmented anti-Houthi forces under a new Supreme Military Committee.

“The intent is to bring those factions into one military command-and-control structure,” Williams says.

“What is on paper is probably different to the reality, but we are seeing groups working together.”

At the same time, Iran’s regional position has been weakened, while Israeli, US and British-led strikes have degraded Houthi military capabilities.

Together, Williams says, those factors may encourage the Yemeni government and its allies to “start testing the waters”.

The Supreme Military Committee could develop the capacity for an anti-Houthi offensive within six to 12 months, renewing fighting around front lines in Marib, Taiz, Shabwah and Al Bayda.

Any renewed conflict would also expose Saudi Arabia to Houthi retaliation. Houthi leader Abdul Malik al-Houthi has warned that the kingdom’s oil facilities and other vital infrastructure will be targeted if Riyadh escalates.

The threat is credible. Attacks claimed by the group against Abqaiq and Khurais in 2019 temporarily removed more than half of Saudi crude production, while further strikes hit energy facilities in 2022.

Saudi Arabia can now transport much of its oil across the kingdom to Yanbu on the Red Sea, bypassing Hormuz.

But exports must still pass through waters vulnerable to Houthi attack or take the longer and more expensive route through the Suez Canal.

The Houthis do not need physically to seal Bab el-Mandeb to cause serious disruption. Missile or drone attacks could persuade shipping companies and insurers that the risks are unacceptable, forcing vessels around the Cape of Good Hope.

For now, neither Tehran nor the Houthis has an interest in provoking a large-scale Saudi intervention. But limited attacks and retaliation could gradually acquire their own momentum.

“This is a classic case of going from managed escalation,” Williams says.

“It keeps ramping up and neither side is particularly good at finding the off switch.

“It could gradually erode the current military stalemate and create the conditions for broader and more intense fighting during the second half of 2026.”