The blockade of the Strait of Hormuz has triggered an oil and ⁠gas crisis that is "more serious than ​the ones ⁠in 1973, 1979 and 2022 together," Fatih Birol, the head of the International Energy Agency (IEA), said on Tuesday.

"The world has never experienced a disruption to energy supply of such magnitude," Birol said in an interview with the French newspaper Le Figaro.

He said the European countries, as well Japan, Australia and others will suffer, but the countries most at risk were developing nations which will suffer from higher oil and gas prices, higher food prices ⁠and a general acceleration of inflation.

The conflict has spurred worries about ​stagflation – high inflation with weak or ​slow growth – upending the global interest rates ⁠outlook.

The IEA member countries agreed last month to release ​part of their strategic reserves. Some of this ​had already been released and the process continues, said Birol.

In ⁠reaction ‌to ‌the strikes by Israel ⁠and the U.S., ‌Iran has almost entirely blocked the traffic in ​the Strait of ⁠Hormuz, through which about 20% ⁠of world oil and gas ⁠regularly flows, creating ​a surge in energy prices.

It later said it would allow transits by vessels that had no U.S. ‌or Israeli links. As a result, some tankers have managed to cross the narrow waterway, but energy markets have still experienced unprecedented disruption.

International Brent crude rose by 60% in March, a record monthly increase.

U.S. President Donald Trump has threatened to rain "hell" on Tehran unless it makes a deal by the end of Tuesday that would allow traffic to start moving through the Strait of Hormuz.

Iran said it wanted a lasting end to ​the war, instead of a temporary cease-fire and pushed back against pressure to reopen the waterway.

The IEA earlier described the conflict as the world's biggest energy supply shock yet, citing more than 12 million barrels per day of regional shut-ins and damage to about 40 energy facilities.