The West’s international energy watchdog has warned that oil stockpiles were being drained at a record rate last month as the US’s war in Iran continues to choke supply in an “unprecedented” supply shock. The International Energy Agency revealed that around 4m barrels of oil a day were tapped from back-up supplies in April, within a detailed report on the global market. It said: “More than ten weeks after the war in the Middle East began, mounting supply losses from the Strait of Hormuz are depleting global oil inventories…