Iran said Monday it had fired upon an American naval vessel on the first day of a bid by Washington to force open the Strait of Hormuz to global shipping.

The semiofficial Fars News Agency, which has close ties to the Islamic Revolutionary Guard Corps (IRGC), initially claimed an unidentified US ship was hit by two missiles near the port of Jask, southeast of the strait, after ignoring orders to halt.

US Central Command (CENTCOM) denied the claim on social media, saying on X: “No US Navy ships have been struck. US forces are supporting Project Freedom and enforcing the naval blockade on Iranian ports.”

A senior Iranian official then told Reuters that Tehran had fired a warning shot and that it was unclear whether the warship had been damaged.

Iran has frequently claimed to have struck American warships since the beginning of the conflict Feb. 28, even alleging the USS Abraham Lincoln aircraft carrier was hit in March, only for CENTCOM to state on that occasion that “the missiles launched didn’t even come close.”

President Trump announced Sunday on Truth Social that the US would “guide” ships out of the strait under an initiative called Project Freedom, warning that Iranian efforts to block them “will, unfortunately, have to be dealt with forcefully.”

The Iranians responded by warning that any ships attempting to pass through the waterway must coordinate with them first, and that any effort to force open the strait would be resisted.

“We warn that any foreign military force — especially the aggressive US military — that intends to approach or enter the Strait of Hormuz will be targeted,” Maj. Gen. Pilot Ali Abdollahi told state broadcaster IRIB.

Meanwhile, the US has told shipping companies they could face sanctions for paying Iran to pass through the strait and has maintained a naval blockade on Iranian ports since April 13.

As of Sunday, 49 commercial ships had been forced to turn back by the embargo, according to CENTCOM.

White House officials have publicly said they hope the blockade helps bring Iran back to the negotiating table, with Treasury Secretary Scott Bessent predicting Sunday that Tehran was “going to have to start shutting in wells, which we think could be in the next week” due to the Islamic Republic’s oil storage facilities filling up.

Caught between the two warring nations, hundreds of vessels have opted to simply remain in place and try to wait out the conflict.

According to the International Maritime Organization, up to 20,000 crew members have been stranded on about 2,000 vessels — including oil and gas tankers, cargo vessels and cruise liners — in the Strait of Hormuz since the start of Operation Epic Fury.

“There is no precedent for the stranding of so many seafarers in the modern age,” Damien Chevallier, director of the IMO’s maritime safety division, told reporters March 31.

On Monday, the US-led Joint Maritime Information Center advised ships to cross the strait via Oman’s territorial waters, saying it had set up an “enhanced security area.”

The center also warned vessel masters that attempting to use the usual routes “should be considered extremely hazardous due to the presence of mines that have not been fully surveyed and mitigated.”

The American military has said the initiative might involve guided-missile destroyers, more than 100 aircraft and 15,000 service members but has not specified what kind of assistance or escorts it would provide ships.

With Post wires