Iran has declared the Strait of Hormuz closed to shipping, a claim that emerged after a night of intense US airstrikes and subsequent retaliatory attacks by Tehran against US allies in the Gulf region.

The assertion, reported by the Australian Financial Review, marks a dramatic escalation in the ongoing conflict and introduces immediate physical risk to global energy supply chains.

Markets reacted swiftly to the news, with energy prices surging on fears of a prolonged disruption to oil flows.

The Strait of Hormuz handles roughly a fifth of the world's oil consumption, and any credible threat to its openness sends shockwaves through crude and natural gas benchmarks.

Traders are now pricing in a significant supply shock, with volatility spiking across commodity futures.

The development follows a broader retaliatory campaign by Iran against US military assets in the Gulf, which has already triggered sirens across multiple Middle Eastern countries.