DUBAI-Iran-backed Houthi militants seized a strategic island in the Bab al-Mandeb strait and a town along its mainland coast on Friday, taking effective control of one of the world's most important shipping chokepoints after a rapid offensive.

The gains raised the stakes in the broader conflict sparked by the U.S. and Israel war with Iran. They came despite long-running Saudi military support for forces opposing the Houthis and, people familiar with the matter said, U.S. technical support and intelligence in the fighting.

The Houthis took control of Perim Island, Saudi and Yemeni officials said. The volcanic island sits inside the Bab al-Mandeb and divides the narrow waterway into two shipping channels, giving whoever holds it a powerful position to threaten vessels entering or leaving the Red Sea. The militants also reached ?the Yemeni ?town of Dhubab, which sits ?directly ?on the strait.

The seizures capped a series of swift Houthi gains. The militants captured the strategic port city of Mokha on Thursday and are pushing along other stretches of Yemen's Red Sea coast.

The Houthi advance further threatens Saudi oil exports just as Iran is constraining shipments through the Strait of Hormuz on the other side of the Arabian Peninsula. Riyadh has relied on moving crude across the country to Red Sea ports to bypass Hormuz, but escalating Houthi attacks are putting that alternative route under growing pressure.

"The progress made by the Houthis raises the risk of greater disruption to Saudi Arabia's oil exports," said Hamad Hussain, an economist at Capital Economics. "The Houthis now appear to be in a better position to strike oil tankers and cause more damage to energy infrastructure on land."

Tensions have been rising in the region since the collapse of a mid-June preliminary peace deal between the U.S. and Iran. Iran has fired missiles at U.S. warships, including an aircraft carrier, and has continued to strike ships in the Strait of Hormuz. The U.S. has hit Iranian tankers and sites in Iran.

Foreign ministers from Gulf Arab states including Saudi Arabia were weighing a meeting with Iran's foreign minister next week in Oman, the first since the war erupted in February, to discuss the future of the Strait of Hormuz, people familiar with the matter said. The Gulf states believe an interim deal can be reached with Tehran to ease the tension over the strategic waterway and allow ships to pass freely, they said. Oman is hoping that the meeting, expected to be held Monday in the southern Omani city of Salalah, would pave the way to complete a deal under which vessels would enter the strait through Iranian waters and exit mostly through those controlled by Oman.

The Houthi gains complicate the U.S. campaign against Iran. Control of the Bab al-Mandeb gives an Iranian ally greater ability to threaten a second major maritime chokepoint, raising pressure on Washington to protect Red Sea shipping when U.S. forces are already struggling to end Iran's hold on the Strait of Hormuz.

The escalating fighting in Yemen, some of the worst the country has seen in years, shows how the war with Iran is spreading instability across the Middle East and raising the risk of further strains on global energy flows after Iran's disruption of the Strait of Hormuz triggered the biggest oil-supply shock in recent history.

Separately, Saudi Arabia's East-West pipeline was hit overnight, a person familiar with the matter said. Another person said the pipeline, which carries crude from Saudi Arabia's producing heartland on the Persian Gulf to Yanbu on the Red Sea, bypassing the blockage in Hormuz, was shut down.

NASA satellites that track wildfires detected possible blazes overnight along the pipeline south of Medina. The locations over the past month haven't shown high heat readings there.

Saudi Arabia's oil industry was already reeling. The kingdom's crude oil production fell to its lowest level in more than three decades last month, dropping by 2.3 million barrels a day to six million barrels a day in August, the International Energy Agency said in a report Friday. Saudi Arabia produced around 9.4 million barrels a day on average last year.

The Houthis, part of Iran's network of allied militias across the Middle East, had largely stayed out of the current U.S.-Iran war until July, when a preliminary deal between Washington and Tehran and a separate long-running ceasefire in Yemen both began to fray. The group then declared a maritime blockade of Saudi Arabia and began attacking Saudi shipping in the Red Sea.

Yemen's civil war began after the Houthis swept out of their northern strongholds and seized the Yemeni capital, San'a, in 2014. Saudi Arabia intervened the following year and fought for years to dislodge them. It later scaled back its direct role while continuing to back Yemen's internationally recognized government.

The conflict ultimately left the country divided, with the Houthis controlling much of the north.