Greater Force

Iran's top negotiator on Sunday threatened a more forceful response to any further US attacks after Tehran targeted American warships in their latest round of clashes. The exchanges of fire, which began with US raids last week, come amid a deadlock in the six-month war between the two sides. Iran has maintained its stranglehold on the strategic Strait of Hormuz while Washington continues a counter-blockade of Iranian ports.

"The Americans must have understood that the era of proportionate responses has come to an end," said Iran's parliament speaker Mohammad Bagher Ghalibaf, who has acted as chief negotiator. "Any aggression against Iran's interests and security will receive a faster, more intense and more painful response."

Oil tankers destroyed

On Saturday, Iran unsuccessfully fired at two American warships. In response, the US military permanently disabled three oil tankers linked to the Iranian Guards. "Following Iran's failed attacks, CENTCOM permanently disabled the IRGC crude oil carriers," CENTCOM said, releasing video showing large fireballs after projectiles slammed into the ships.

Iran quickly retaliated, with the Guards saying their naval forces targeted three oil tankers on the "unauthorised route" of the Strait of Hormuz. CENTCOM commander Admiral Brad Cooper said: "If you shoot at two of our ships, we will impose an even higher economic cost, taking out three of yours." The Iranian foreign ministry called the attacks on its oil tankers "illegal and aggressive actions".