TOKYO - Oil prices spiked after US President Donald Trump said he would reimpose a blockade on Iranian ships transiting the Strait of Hormuz and demand payment for all other cargo moving through the waterway.Brent crude surged 9.6 per cent to close at US$83.30 per barrel on July 13. It was the global oil benchmark’s biggest daily rise since May 2020. US West Texas Intermediate soared 9.4 per cent to settle at US$78.14.Trump demanded a 20 per cent reimbursement on cargoes – or roughly US$30 million (S$38 million) on full supertankers carrying oil – as US forces launched a third night of strikes against Iran that may last several more days. Crude has rebounded to its highest in a month, reversing a second-quarter drop of about 30 per cent, as the escalating conflict rekindles concerns over supplies from the Middle East. Iran had managed to export at least 57 million barrels of crude during a brief gap between two American naval blockades, highlighting what’s at stake for the global oil market now that restrictions are being reimposed.“They were just shipping oil out at unbelievable rates,” said Jay Hatfield, chief executive officer at Infrastructure Capital Management. “We think we’ll hang around this US$80 level, unless there’s some movement one way or another on the strait. But I don’t think we’ll go to, like, US$90 or US$100. And if the strait reopens, we’ll go to US$60 in one hell of a hurry.”Iran’s army targeted US assets in Kuwait with drones and struck “a hostile vessel” with cruise missiles, the semi-official Fars news agency reported, citing an army statement.Earlier on July 13, Tehran said the agreement with Washington has “undoubtedly entered a crisis phase” and that it won’t abide by its terms as long as the other party violates commitments. Iranian Foreign Minister Abbas Araghchi mocked Trump’s toll proposal.“Iran has always been the GUARDIAN of the Strait and will remain so FOREVER,” he posted on X. “20 per cent is of course too much. We will be fair.” BLOOMBERG