Tehran: Iran signalled a sharp escalation in the ongoing standoff with the United States, with a statement attributed to Supreme Leader Mojtaba Khamenei asserting that the country’s navy is prepared for confrontation, even as Iranian forces reportedly opened fire on a tanker in the strategically vital Strait of Hormuz.

In a statement carried on his Telegram channel, Khamenei, who has not been seen in public since before the start of the war, said Iran's "brave navy stands ready to make the enemies taste the bitterness of new defeats".

The warning came amid rapidly rising tensions in the Strait of Hormuz, where Iran has reimposed restrictions on maritime movement in response to a US blockade on its ports and shipping.

According to the British military’s United Kingdom Maritime Trade Operations centre, two gunboats from Iran’s Revolutionary Guard fired on a tanker attempting to transit the strait on Saturday. The agency reported that the vessel and its crew were safe, though it did not disclose further details about the ship.

Iran’s joint military command confirmed tightening control over the crucial waterway, stating that “control of the Strait of Hormuz has returned to its previous state ... under strict management and control of the armed forces.” It further warned that restrictions would remain in place as long as the US blockade continues.

The latest developments mark a dangerous turn in the seven-week-long conflict, with both sides engaging in tit-for-tat measures that have disrupted one of the world’s most critical oil transit routes. Iran had earlier allowed limited passage for select vessels but has now resumed blocking crossings, except for those it authorises.