Oil prices leapt to the highest level in a month after Donald Trump said the US would reinstate its naval blockade of Iran and charge a 20% fee on cargo passing through the Strait of Hormuz. Brent crude settled at $83.30 a barrel, a nearly 10% jump, as tensions between Washington and Tehran flared.

Trump declared on Truth Social that the strait would remain open for all countries, but the US would act as its “guardian” and be reimbursed for the costs of securing passage. The U.S. military announced it would begin enforcing the blockade against ships heading to or from Iranian ports the following day.

Iran’s military responded with warnings that it would not allow US interference and that it would counter any disruption. Shipping companies fear higher insurance premiums, and Province‑based analysts note that the 20% levy could add about $16 to each barrel of crude that transits Hormuz.

The spike in oil prices pushed 10‑year Treasury yields to 4.61% and pulled the S&P 500 down 0.8% and the Nasdaq 1.6%. International Maritime Organization officials stressed that there is no legal basis for mandatory tolls on international navigation routes.