It took Houthi rebels less than 48 hours to seize Yemen’s Red Sea coast from pro-government forces in a resounding blow to U.S. interests and Washington’s regional allies.
But the Houthis didn’t do it alone. Iranian Revolutionary Guard advisers were in the field helping direct the battle, people familiar with the offensive told The Associated Press, marking Iran’s most direct intervention in favour of its longtime ally since Yemen’s civil war erupted in 2014.
The intervention shows how Iran has built the Houthis into a major regional partner able to open a new front in the wider war with the U.S.
The rebels’ biggest land grab in years, along with the closure of a key Saudi pipeline, strengthened their ability to choke off Saudi Arabia’s oil exports, pushing up global fuel prices and giving Iran greater leverage. The United States has seemed reluctant to help its ally Saudi Arabia, even as the Houthis have gained momentum in Yemen’s revived civil war.
The AP spoke to 10 officials and soldiers to assemble an account of the Houthi offensive. They included a senior Houthi official, two regional officials, a top Yemeni military commander and a member of Yemen’s ruling presidential council. They spoke on condition of anonymity to discuss internal decision-making.
The Houthis’ swift, 115-kilometre (75-mile) assault exploited divisions among forces allied with Yemen’s Saudi-backed, internationally recognised government. The Houthis penetrated the internal communications of one of the main forces, the National Resistance, allowing them to track its movements and sow confusion.
As pro-government forces beat a frantic retreat, the leader of the National Resistance fled to Saudi Arabia. The key port city of Mokha was abandoned as residents left in the night, allowing the Houthis to roll in unopposed on September 10. Their seizure of strategic islands nearby further enhanced their ability to attack Saudi oil shipments in the Red Sea.
The Houthis vs Saudi Arabia | The new lords of the Red Sea
Iran had been building up the Houthis’ capabilities
The Houthis had not conducted a major campaign along the coast since 2017, when government forces drove them out of the area. Since then, the Houthis have focused on trying to capture the oil-rich province of Marib in central Yemen.
A truce took hold in 2022. The following year, the Houthis began attacking Red Sea shipping over the war in Gaza, attacks that continued until a punishing US bombing campaign in 2025. After the US and Israel attacked Iran in February, the Houthis largely kept to the sidelines.
Last year, Iran began providing the Houthis with stepped-up training and logistical support on more advanced missiles, drones and uncrewed attack boats, said Mzahem Alsaloum, a security analyst who has followed Iranian-backed groups for nearly a decade and now runs a private intelligence firm.
In July, the Houthis renewed their attacks on Saudi Arabia after accusing it of striking the airport in the rebel-held capital, Sanaa. That strike appears to have been aimed at halting a flight from Tehran.
Alsaloum and the senior Houthi official said the Iranian flight, which later landed, brought Revolutionary Guard advisers, who joined other advisers from the Guard — and Iran’s Lebanese ally, Hezbollah — already based in Yemen.
Iranian advisers assumed a larger role in the offensive
In early August, the Houthis resumed attacks on government forces, focusing on the city of Taiz, in the mountains overlooking the coast, and firing missiles and drones at Mokha.
The Houthi official said Iranian advisers had previously focused on strategic planning and were not in the field. But in the latest escalation, they were “present at all levels,” he said, including planning tactical manoeuvres and working with front-line commanders.
The two regional officials, who are regularly briefed on the latest developments in Yemen, also said Iran provided direct support that helped the rapid advance.
Alsaloum said that in addition to helping in a command role, the Iranian advisers analysed communications and satellite intelligence, capacities the Houthis were lacking.
Iran’s UN mission did not respond to requests for comment.
Pro-government forces were divided
The National Resistance, with some 30,000 fighters, was the strongest pro-government force along the coast. But it had not been involved in major fighting since 2017.
For a month, Houthi forces bombarded its positions with 130 ballistic missiles and 145 suicide drones, according to a National Resistance spokesman, Maj. Gen. Sadiq Dwaid. He said its fighters were stretched over 170 kilometres (100 miles), from Mokha into the mountainous interior, against what he estimated were 75,000 Houthi fighters.
In early September, the Giants Brigade, another militia, came to its aid, helping it to temporarily push back the rebels. But the Giants Brigade had not coordinated with the National Resistance, angering its field commanders, one government official said.
The two forces had a long-standing rivalry rooted in the past struggle between Saudi Arabia and the United Arab Emirates over control of the anti-Houthi movement. That struggle led to the UAE abruptly pulling out of Yemen in January.
There was no “unified command,” said the senior military official. “This was a priceless opportunity for the Houthis.”
A swift advance led to a panicked retreat
On September 9, the Houthis advanced south toward Mokha through a narrow mountain valley, heavily bombarding their opponents.
Having breached their communications, the Houthis were able to listen in and exploit divisions, one of the government officials said, adding that National Resistance leaders lost contact with several field commanders.
By the afternoon, the Houthis had seized the mountain road and a nearby military base, cutting off government supply lines to Mokha. Lt. Gen. Tariq Saleh, the leader of the National Resistance, was forced to flee and then took refuge in Saudi Arabia.
At around 6 p.m. that night, orders went out to National Resistance field units to retreat back to Mokha. When thousands of fighters began arriving, the forces stationed in the port city thought a major Houthi attack was imminent and began to flee, two National Resistance fighters told the AP.
A Mokha resident, Issa Gubwani, said he saw fighters in military vehicles and pickups streaming out of the city. “They left us to face our fate,” he said. Tens of thousands of residents joined the exodus.
The Houthi official said that when the rebels rolled in early on September 10, “the city was empty.”
Government forces are trying to regroup
The senior government military official said Yemeni forces were stunned that Saudi warplanes didn’t strike the Houthis as they advanced on Mokha. The Saudi government media office did not respond when asked for comment.
The Houthis seized weapons and military equipment, including armoured vehicles, rockets, artillery shells and ammunition, most of it from the UAE and Saudi Arabia, two government officials said. The rebels displayed some of the captured weapons in a televised parade.
The National Resistance said it lost 500 fighters in the battles; that could not be independently confirmed. The Houthis have not announced their losses.
As government forces work to regroup, supporters of the various militias have been trading blame and accusations of treason online. The Houthis are meanwhile building defences around the newly captured territories, according to the Houthi official.
“Losing the West Coast is not the end of the battle; rather, it marks the beginning of a fiercer battle,” Brig. Gen. Walid Ziyad, a senior National Resistance commander, declared on social media.
