At least three foreign oil tankers that attempted to cross the Strait of Hormuz “without authorisation” have turned back after a warning from Iran’s Islamic Revolutionary Guard Corps (IRGC), Al Jazeera reports citing state TV.

Yesterday, a Singapore-flagged vessel came under attack from an unknown projectile, prompting the UN to call off its mission to rescue 11,000 sailors in the Strait of Hormuz.

Tehran has not claimed the attack, but has issued multiple warnings against transiting the waterway without Iran’s authorisation.