War in the Middle East is escalating as Yemen’s Iranian-backed Houthi rebels launch a series of attacks on U.S. allies and shut down another vital shipping route.
The Houthis, one of the most powerful Iranian-backed militias in the region, entered the war by firing missiles at Israel in March, a month after Israel and the United States attacked Iran. The group is currently engaged in a gunfight with Yemen’s internationally recognized government and has attacked Saudi Arabia after a four-year de facto ceasefire with the country.
The escalation comes amid uncertain maritime security in both the Strait of Hormuz and the Red Sea, with conflicting accounts from Iran and the United States over whether direct negotiations were taking place to reopen the waterway.
The attack also raises the threat of a new all-out war in Yemen. The last war that began in 2014 has left the country facing the world’s worst humanitarian crisis.
Here’s what we know about this escalation and how it could affect the US-Iran war.
Yemen’s war dates back more than a decade and is primarily a conflict between the Houthi rebels and the Saudi-led coalition supporting the internationally recognized government.
The Houthis belong to Yemen’s Zaidi Shia Muslim minority, officially known as Ansar Allah, or “Partisans of God.” After the 2011 Arab Spring, Yemen occupied the northern provinces and then the capital, Sana’a, which it still occupies, along with much of Yemen’s Red Sea coast.
In the process, they received weapons and technology and became part of Iran’s “Axis of Resistance,” a network of allied extremist groups across the region.
Saudi Arabia, a U.S. ally, launched a major offensive against the militants in 2015 after spending seven years unsuccessfully trying to dislodge the Houthis from northern Yemen. The ensuing conflict caused one of the world’s worst humanitarian crises.
A ceasefire agreement was signed in 2022, but it did not lead to peace. That same year, an internationally recognized Yemeni government was established in Saudi Arabia, operating under the Saudi-backed Presidential Leadership Council (PLC). Riyadh has sought to support the government with air and naval operations, as well as limited troop deployments.
Since then, Saudi Arabia has maintained an economic and air blockade on Houthi-controlled areas, which the group has been trying to break in recent weeks.
Despite efforts to avoid conflict, Saudi Arabia has become embroiled in war. Riyadh came under a barrage of missile fire during the war and continues to face attacks from Iranian-backed groups in Iraq and the Houthis in Yemen.
The Houthis have emerged as a particular threat to Saudi Arabia, targeting oil tankers and blocking Saudi shipping in the Bab al-Mandeb Strait at the base of the Red Sea, a key maritime trade route.
Experts say Yemeni rebels were seizing an opportunity to recoup some of their losses in the Iran war. Its values are tied to those of Iran, but it has its own reasons for fighting Saudi Arabia.
Nasr al-Din Amer, a member of the Iran-backed Houthi politburo, told CNN late Friday night that the group does not need orders from Iran to step up its conflict with Saudi Arabia. Amer said the Saudi attack on the group, which controls large swathes of western Yemen, including the capital Sanaa, was sufficient reason for military action against Riyadh’s forces.
He said Saudi Arabia’s economic and air blockade of Houthi-held areas had “created the world’s worst humanitarian crisis.” “These reasons alone are enough to compel us to act more decisively than ever before. We don’t need any other agenda.”
Hans Grundberg, the UN special envoy for Yemen, warned on Friday that recent attacks by the Houthis targeting Saudi Arabia and Yemeni government forces, as well as new attacks on commercial shipping in the Red Sea and Gulf of Aden, mean Yemen faces the greatest risk of a flare-up of the conflict since the UN-brokered ceasefire in April 2022. He called on all parties to exercise utmost restraint.
Danny Sitrinowitz, head of Israel’s military intelligence agency’s Iran branch, said the conflict between Saudi Arabia and the Houthis is not over yet, adding that the group appears to have crossed a critical threshold.
“At the heart of Riyadh’s problem is the fact that the Houthis appear to have crossed political and military lines. They are no longer willing to return to a status quo where Saudi Arabia can impose or support a blockade of maritime and land areas under their control without facing retaliation,” he wrote to X.
The Houthis appear to be following the logic of Iranian leaders and believe that “time and strategic asymmetries will work in their favor,” Citrinovic said.
For Riyadh, becoming embroiled in a broader conflict would be a risky and potentially costly option. Over the past decade, the focus has been on opening the country to foreign investment and turning it into a regional economic power. This led to a policy of easing tensions with Iran even before the war, leading to an agreement mediated by China in 2023.
This strategy is currently on life support as Saudi Arabia is caught in the middle of a storm. Confronting an unpredictable enemy adept at three-pronged asymmetric warfare is a nightmare for military planners.
On Thursday, a Saudi official told CNN that the kingdom was preparing for “multiple coordinated attacks” by Iraqi militia factions and the Iranian-backed Houthis.
The official cited “multiple intelligence reports” from Saudi Arabia, the United States and regional countries indicating that some Iraqi militias, “in coordination with the Houthis” and under the leadership of Iran’s Islamic Revolutionary Guards Corps (IRGC), are planning to attack Gulf states “in the very near future.”
The official expressed alarm Thursday, saying the reports came as Saudi Arabia seeks de-escalation and negotiations involving Iran appear to be moving in the right direction.
The recent attacks and potential attacks have forced Riyadh to make “unpleasant choices,” Citrinovic wrote. “Escalation could lead to another endless war, the cost and end state of which is difficult to predict. However, significant concessions could strengthen the Houthis politically and militarily and pose an even more formidable threat in the future.”
“In other words, Saudi Arabia is caught between deterrence and mitigation,” he said. “Neither path offers a clear strategic victory.”
The rebels on Thursday claimed to have carried out a “massive” military operation targeting Saudi forces in multiple regions of the country using ballistic missiles and drones.
The Houthis did not provide evidence for that claim, but Reuters reported earlier in the day, citing government sources, that at least 30 Yemeni government troops were killed in Houthi attacks on military camps in Marib and Hadramawt provinces.
On Friday, the Saudi-led military coalition supporting Yemen’s internationally recognized government said 11 civilians were injured in a Houthi attack in the Najran region south of the Saudi border.
However, Riyadh is working to strengthen its defense strategy. On Friday, Saudi Arabia, Turkey and Pakistan signed a mutual defense agreement that stipulates that an attack on either country will be “considered an attack on all countries.”
It was a landmark agreement between the three countries that has helped stall diplomatic efforts to end hostilities between the United States and Iran.
This escalation poses a dangerous and costly threat to both Saudi Arabia and Yemen.
For Riyadh, the resurgent Houthi threat is thwarting attempts to transport millions of barrels of oil from the Persian Gulf to the Red Sea for export, as the Strait of Hormuz remains effectively closed.
Rahul Chaudhary, vice president of upstream research at Rystad Energy, said Saudi oil exports through the Bab al-Mandeb Strait have been cut by at least half since the Houthis declared a blockade of Saudi ships passing through the waterway.
Up to 1.5 million barrels per day can now pass through the strait, he told CNN earlier this week, far lower than the 3.2 million barrels per day seen earlier in the conflict. Before the war, Saudi Arabia produced about 10 million barrels per day.
Still, state-owned Saudi Aramco benefited from high global oil prices, reporting a profit of $33 billion in the second quarter, a 33% increase compared to the same period in 2025.
However, Chaudhary points out that such results “cannot be maintained forever.” He said Aramco’s numbers were partly driven by oil now sold from reduced stockpiles, adding that prices, while volatile, were lower than in the early stages of the conflict.
For Yemen, a series of attacks risks pushing the country back into full-scale civil war.
In the final stages of the internal conflict, the United Nations has designated Yemen the world’s worst humanitarian crisis, with more than 22 million people, three-quarters of the population, in dire need of aid and protection.
The nine-year war has killed thousands of people, destroyed the economy and left tens of thousands of Yemenis living in hunger, according to the United Nations.
A resurgence of fighting risks plunging the country back into the throes of an even worsening humanitarian and economic crisis.
