The head of the International Energy Agency said on Monday that at least 40 energy assets across nine countries in the Middle East have been “severely or very severely” damaged since the Iran war began, raising fears of prolonged supply disruptions.

Speaking at the National Press Club in Australia’s capital, IEA Executive Director Fatih Birol said damage to oil and gas fields, refineries and pipelines across the Middle East would take some time to repair.

His comments come as market participants closely monitor threats from the U.S. and Iran over energy facilities as the sprawling regional conflict enters its fourth week.

The Iran war has severely disrupted energy trade flows through the strategically vital Strait of Hormuz, creating what the IEA says is the largest supply disruption in the history of the global oil market. The global supply of liquefied natural gas (LNG) has also been reduced by roughly 20% since the conflict began on Feb. 28.

Birol said the fallout from the Iran war is equivalent to the two major oil crises of the 1970s and the 2022 gas crisis “put together.”