The U.S. strikes came after a cargo ship was attacked in the Strait of Hormuz.
President Donald Trump announced "major combat operations" against Iran on Feb. 28, with massive joint U.S.-Israeli strikes targeting military, government and infrastructure sites.
Delegations from the U.S. and Iran entered negotiations last month aimed at a war-ending deal based on a memorandum of understanding signed by both countries.
The U.S. and Iran nonetheless exchanged limited strikes in late June despite the signing of the memorandum and amid the continuation of peace talks.
In a post on social media in response to U.S. Central Command announcing a third round of strikes on Iran, Defense Secretary Pete Hegseth wrote: "Iran made a poor choice. Now they pay."
The U.S. military launched another set of strikes in Iran Saturday night, U.S. Central Command said in a statement.
The U.S. strikes came after Iranian forces "blatantly attacked M/V GFS Galaxy, a Cyprus-flagged container ship transiting the Strait of Hormuz," CENTCOM said in a statement posted on X.
"A civilian crew member is missing and the vessel is unable to continue the journey due to an onboard fire and significant engineroom damage," CENTCOM said.
"Iran was provided yet another opportunity to demonstrate adherence to the Memorandum of Understanding after being held accountable for earlier attacks on commercial vessels but has again failed," it added.
Iran says the ship was moving through the strait in an "unapproved route" and was hit by a "warning shot."
-ABC News' Shannon Kingston
The Islamic Revolutionary Guard Corps' navy has announced that the Strait of Hormuz will be closed until further notice and claimed a commercial vessel transiting the waterway was hit and "halted" by a "warning shot" it fired, according to Iranian media.
The statement also said that any U.S. or allied response would be met by "severe" retaliation.
Iran's Islamic Revolutionary Guard Corps said in a statement that was read on state run TV Saturday several ships reportedly used unapproved routes and ignored warnings from the IRGC navy.
-ABC News' Shannon Kingston
As talks in Oman wind down, the key delegations are departing without any signs of an immediate breakthrough -- but there’s still a chance that could change in the coming hours, according to a U.S. official and another source familiar.
Public statements from Iranian Foreign Minister Abbas Araghchi and his Omani counterpart indicate only that navigation through the Strait of Hormuz was discussed during the meeting -- obviously falling well short of the Trump administration’s demand for a public statement from Iran declaring the Strait of Hormuz is fully open and vessels transiting through it are safe from attacks.
However, the sources said Araghchi is returning to Iran with an Omani proposal for managing the Strait of Hormuz that would see the southern lane of the waterway operate unimpeded, but require ships traveling in the northern lane, which runs through Iran’s territorial waters, to receive approval from -- but not pay a toll to -- Tehran.
Other proposals for dividing the waterway were also considered, the sources added.
At this point, it’s unclear if the Omani plan has the full support of the Trump administration or if it can win approval from Iranian leadership. But it was always expected that the Iranian delegation in Oman would need to return to their country to consult top levels of leadership before moving forward or even issuing a more substantial statement, leaving the door open for now.
-ABC News' Shannon K. Kingston
