Iran strikes cargo ship in Strait of Hormuz, defying U.S. ultimatum

Iran's Islamic Revolutionary Guard (IRGC) Corps fired a missile at a commercial cargo ship attempting to transit the Strait of Hormuz, hitting and damaging the vessel, according to U.S. official.

In a statement, the IRGC declared the strait to be "closed until further notice."

Why it matters: The attack came one day after the Trump administration demanded that Iran publicly guarantee safe passage through strait, a key U.S. condition for halting the cycle of fighting between the two countries.

It also came hours after Irani's foreign minister, his Omani counterpart and Qatari officials concluded a day of negotiations in Muscat aimed at resolving the standoff.

The Hormuz crisis has threatened to collapse the memorandum of understanding reached between the U.S. and Iran last month, with President Trump declaring the ceasefire "over" this week.

State of play: The IRGC claimed it had warned several ships not to use what it described as an unauthorized route through the strait, and fired a "warning shot" after the cargo ship failed to change course.

"Following this incident ... the Strait of Hormuz will be closed until further notice and until the end of the American interventions in this area, and no vessels will be allowed to pass through it," the IRGC said.

Zoom in: Oman proposed fully reopening both shipping lanes through the Strait of Hormuz during Saturday's talks, according to a diplomat briefed on the negotiations.

Under the proposal, the southern route through Omani waters would reopen without any requirement for prior approval, restoring the rules that were in place before the war, the diplomat said.

Iran's delegation could not get approve for the proposal in Muscat and took it back to Tehran for further internal discussions, according to the diplomat.

The commercial cargo ship struck by the IRGC was transiting the southern route that Oman had proposed reopening without restrictions, according to the U.S. official.

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