Oil prices have risen sharply after the two-month window for a US-Iran peace deal expired on Monday with the conflict still unresolved, and Donald Trump threatened to bomb Oman if it "gets in the way" of his efforts to end the war. Trump also demanded Iran "put up the white flag of surrender", while Tehran signalled it would adopt a more aggressive military posture, raising fears of a prolonged disruption to shipping through the strategically vital Strait of Hormuz.

Brent crude rose above $90 a barrel for the first time since 30 July, trading at $91.63 on Tuesday morning, as analysts warned the market was shifting from pricing a temporary disruption to a sustained one. A cargo ship was attacked in the strait early on Tuesday, and an Iranian military spokesperson warned vessels would "find several beautiful holes in their hulls". Ship traffic through the waterway, which normally carries roughly a quarter of global seaborne oil, has slowed to just a handful of vessels a day, and analysts cautioned that continued conflict there alongside Russia's war in Ukraine could deliver a "double shock" to energy markets between September and November.