Iran’s Revolutionary Guards Council (IRGC) described US claims that two American merchant vessels had crossed the Strait of Hormuz as “baseless and completely false" on Monday, after the US Central Command (CENTCOM) said the ships had transited the vital waterway earlier.

No commercial vessels or oil tankers have passed through the Strait of Hormuz in the past few hours, and the claims of American officials are baseless and completely false," the Guards stated on Telegram.  

Earlier, CENTCOM said two US-flagged merchant vessels had "successfully transited through the Strait of Hormuz".

It followed up by claiming that "two US-flagged merchant vessels have successfully transited through the Strait of Hormuz and are safely headed on their journey".

The IRGC said the US claims are "outright lies," and warned that any other movements against the instructions of the IRGC Navy "face serious risks."

Iran said earlier Monday that it had fired missiles at a US warship in the Strait of Hormuz, accusing it of “violating maritime security and navigation norms.” The reports said the vessel was forced to turn back.

"Following the Zionist American destroyers' disregard for the initial warning, the Navy issued a warning shot by firing cruise missiles, rockets, and combat drones around the aggressor enemy vessels," Iranian state TV said.

Iran's army commander Amir Hatami, meanwhile, said on X, "American destroyers, using the trick of turning off the radar, were approaching the Strait of Hormuz, but our response was fire."

"Cruise missiles and combat drones took flight. The security of this region is Iran's red line," he added.

CENTCOM head, Brad Cooper, later said during a news conference that Iran has launched multiple cruise missiles, drones, and small boats at ships the US is protecting in the Strait of Hormuz.

He said “each and every one” of the threats had been defeated.

In his call with reporters, Cooper declined to say whether the ceasefire between Iran and the US was over or not, but claimed that it was Iran that “initiated aggressive behavior” in the strait.

He added that the US military helicopters have sunk six small Iranian boats that were targeting civilian vessels in the Strait of Hormuz, claiming that the US has been able to clear a pathway in the Strait that is free of any Iranian mines in an effort to allow commercial vessels to transit the narrow waterway.

Cooper said the US military also has set up a “defensive umbrella” that includes American helicopters and fighter planes to protect the freighters leaving the strait.

Tehran's forces severely restricted transit through the strait to the United States, Israel, and their Western allies in response to the US-Israeli war that began on 28 February, while Washington is maintaining a blockade of Iranian ports.

On Sunday, Trump gave few details in announcing his plan to reopen the vital waterway, where about a fifth of the world’s trade in oil and natural gas typically passes.

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