Pakistan said Monday it had facilitated the transfer of 22 crew members from a U.S.-seized Iranian vessel, describing the move as a "confidence-building measure" amid fragile diplomatic contacts between Washington and Tehran.

The sailors, who had been held aboard the container ship Touska, were flown into Islamabad late Sunday and were due to be handed over to Iranian authorities, according to a statement from Pakistan's foreign ministry.

Iranian state media said Monday that 15 crew members from the Touska had been "returned to Iran," but their whereabouts remained unconfirmed.

The handover comes amid a tense standoff in the Persian Gulf, Strait of Hormuz and Gulf of Oman, where U.S. forces intercepted the Iranian-flagged cargo ship.

Iran condemned the ship's seizure as "piracy" and a violation of an April ceasefire and urged the United Nations to intervene.

Pakistan has positioned itself as a mediator between the U.S. and Iran, hosting the only round of direct talks between the two sides since the U.S. and Israel launched their joint war with Iran on Feb. 28. Islamabad has tried for weeks to orchestrate a second round of talks, but thus far the Trump administration has refused to accept Iran's demands for such negotiations, and Tehran says it won't talk until the U.S. blockade of its ports is lifted.

The transfer of the Touska crew was coordinated with both sides, Pakistan said, reflecting a rare instance of practical cooperation despite wider tensions over sanctions, shipping routes and regional security.

The vessel itself is expected to be returned after repairs. 

CBS/AFP

A spokesperson for the U.S. military's Central Command, Captain Tim Hawkins, told CBS News on Monday that claims by Iranian media outlets that an American warship had been struck by two missiles near the Strait of Hormuz were not true.

Hawkins did not provide any further detail, but he rejected the report by Iran's Fars news agency, which is associated with the Islamic Republic's Revolutionary Guard forces, that U.S. Navy frigate was struck on Monday amid an increasingly tense standoff between the countries in the Persian Gulf.

The U.S. military said it launched an operation Monday under the name "Project Freedom," under which President Trump says commercial vessels stuck in the Gulf can be guided out by the U.S. military via the Strait of Hormuz.

Iran has warned that any ship trying to navigate the narrow strait without its explicit permission will be targeted.

CENTCOM later issued a brief statement on social media reiterating Hawkins' rejection of the Iranian report, saying: "No U.S. Navy ships have been struck. U.S. forces are supporting Project Freedom and enforcing the naval blockade on Iranian ports."

French President Emmanuel Macron has called on the U.S. and Iran to reopen the Strait of Hormuz in a "coordinated" way, indicating that his country won't join an effort announced by President Trump to "guide" commercial vessels out of the Persian Gulf under the threat of Iranian attack.

"What we want above all is a coordinated reopening by the United States and Iran — that is the only solution for reopening the Strait of Hormuz," Macron told fellow European leaders during a meeting on Monday in Armenia.

"We are not going to take part in any military operation in a framework that to me seems unclear," he said.

France and the U.K. have led efforts to build a coalition of nations to deploy military assets to the region to ensure the strait remains open and safe for shipping once peace is secured, but European countries have declined to take up those efforts until a deal is reached to end the war.

Brigadier General Mohbi, a spokesman for Iran's powerful Islamic Revolutionary Guard Corps, warned Monday that any vessel trying to transit the Strait of Hormuz without adhering to the regime's "transit protocols," which require coordination for passage "through designated routes with coordination," will "face serious risks."

"Violating vessels will be stopped with force," said Mohbi in a message shared by Iranian state media. 

It was the latest direct challenge from the Iranian regime to a plan announced by President Trump for a "humanitarian" military operation for American warships to "guide" commercial vessels out of the Persian Gulf via the Strait of Hormuz. 

Dozens of tankers and cargo ships have been stuck in the Gulf for months as Tehran, in retaliation for the joint U.S.-Israeli war against Iran, has declared the strait — long an open international waterway vital to the transport of gas and oil — under its control, and attacked ships that don't get its permission to use it. 

While an ongoing ceasefire between the U.S. and Iran has ended American strikes on the country, the U.S. has imposed a naval blockade of Iranian ports and vessels, which Tehran considers a breach of the truce. Iran has responded by maintaining its threat to commercial shipping, which has kept oil and gas prices high and fueled inflation around the globe.

The United States kicked off an effort to "guide" stranded ships from the Iran-gripped Strait of Hormuz, as it tries to counter economic disruptions that outlasted the peak of fighting with no peace deal in sight.

A day after President Trump announced what he called "Project Freedom," the Joint Maritime Information Center said Monday that the U.S. had set up an "enhanced security area" south of typical shipping routes and urged mariners to coordinate closely with Omani authorities "due to anticipated high traffic volume." The strait sits between Iranian and Omani territory.

The center warned that passing close to the usual routes, known as the traffic separation scheme, "should be considered extremely hazardous due the presence of mines that have not been fully surveyed and mitigated."

The U.S.-led maritime task force's announcement marked the start of the effort to revive traffic and restore confidence among commercial vessels transiting the strait.

The disruption of the waterway through which roughly one‑fifth of the world's oil typically passes has become one of the most enduring consequences of the war that the U.S. and Israel launched Feb. 28. It has squeezed countries in Europe and Asia that depend on Persian Gulf supplies and added new volatility to energy prices for households and businesses worldwide. 

Iran's military said Monday that U.S. forces would be attacked if they entered the Strait of Hormuz, after President Trump announced Washington would begin escorting ships through the blocked waterway.

"We warn that any foreign armed force — especially the aggressive U.S. military — if they intend to approach or enter the Strait of Hormuz, will be targeted and attacked," said Major General Ali Abdollahi of the Iranian military's central command, in a statement carried by state broadcaster IRIB.

"We have repeatedly stated that the security of the Strait of Hormuz is under the control of the armed forces of the Islamic Republic of Iran, and under all circumstances, any safe passage must be coordinated with these forces," he added.

Iran's Revolutionary Guards said Sunday the United States faced a choice between an "impossible" military operation or a deal with Tehran, after President Trump disparaged Iran's latest peace proposal.

Iran's foreign ministry said Tehran had submitted a 14-point plan "focused on ending the war" and that Washington had already responded to it in a message to Pakistani mediators, which Iran was reviewing. 

Project Freedom, the effort announced by President Trump to help merchant vessels get through the Strait of Hormuz, will include "guided-missile destroyers, over 100 land and sea-based aircraft, multi-domain unmanned platforms, and 15,000 service members," U.S. Central Command said Sunday night.

Further details on what the operation would involve were not provided. 

President Trump on Sunday said an effort to guide ships from countries not involved in the war with Iran safely out of the Strait of Hormuz, dubbed Project Freedom, will begin Monday. 

"For the good of Iran, the Middle East, and the United States, we have told these Countries that we will guide their Ships safely out of these restricted Waterways, so that they can freely and ably get on with their business," Mr. Trump wrote on Truth Social.

"In all cases, they said they will not be returning until the area becomes safe for navigation," Mr. Trump wrote.

The president said the effort is a "Humanitarian gesture on behalf of the United States, Middle Eastern Countries but, in particular, the Country of Iran," noting that the ships are running low on food and other essential supplies.

"If, in any way, this Humanitarian process is interfered with, that interference will, unfortunately, have to be dealt with forcefully," Mr. Trump concluded.