Oil markets will enter the “red zone” by July and August as stocks dwindle before the summer travel season amid a shortage of fresh oil exports from the Middle East, the executive director of the International Energy Agency warned on Thursday.

Fatih Birol added that the most important solution to the Iran war energy shock was a full and unconditional reopening of the strait of Hormuz.

Speaking to the London thinktank Chatham House, Birol said it was open to IEA members to release more strategic oil reserves as they had previously in March, and said the IEA stood ready to coordinate. As much as 80% of IEA’s collective reserves have not been released.