British Foreign Secretary Jeremy Hunt said Friday that Iranian authorities have seized two vessels in the Strait of Hormuz, the strategic waterway that has become a flashpoint between Tehran and the West.

Hunt said one of the ships was flying the British flag while the other was sailing under the Liberian flag.

"These seizures are unacceptable," Hunt said, before warning of "serious consequences" if the issue was not resolved quickly.

"It is essential that freedom of navigation is maintained and that all ships can move safely and freely in the region," he told reporters before going into an emergency meeting over the incidents.

Iran's Revolutionary Guard confirmed the seizure of the British-flagged ship, an oil tanker named Stena Impero, which it said was breaching "international maritime regulations."

On Saturday, the Fars news agency cited an Iranian official as saying that the vessel had been involved in an accident with a local fishing boat. Fars said the tanker was taken to the port of Bandar Abbas and that the crew of 23 would remain on board while investigations continued.

Ship 'ignored several warnings'

The owner of the Stena Impero, Swedish-based transport company Stena Bulk, described how Iranian forces took control of the tanker and directed it toward the Iranian coast.

The ship was "approached by unidentified small craft and a helicopter … while the vessel was in international waters," Stena Bulk said in a statement. "We are presently unable to contact the vessel," the company added.

The company said that no injuries had been reported among the crew.

Citing an unnamed military source, Iran's news agency IRNA earlier reported that the tanker had sailed in the wrong direction in a shipping lane and was ignoring warnings.

"The tanker had turned off its tracker and ignored several warnings by the Guards before being captured," the source told the agency.

Second vessel boarded

Separately, multiple Iranian media outlets reported that a Liberian-flagged vessel, Mesdar — owned by Norbulk Shipping UK — was briefly boarded and issued a warning over a environmental regulation.

"Communication has been reestablished with the vessel and [the captain] confirmed that the armed guards have left and the vessel is free to continue the voyage. All crew are safe and well," Norbulk said in a statement, following the incident.

Read more: UK says Iran tanker will be freed, unless it goes to Syria

Retaliation for Grace 1 tanker?

Iran's move comes after Britain detained an Iranian tanker, Grace 1, near Gibraltar on July 4. A senior Iranian official then threatened "reciprocal action" over the incident.

A few days later, the UK accused Iranian forces of trying to capture one of its cargo vessels, forcing a Royal Navy warship to intervene. That prompted Iran's Supreme Leader, Ayatollah Ali Khamenei, to accuse the "vicious British" of "piracy" and vow retaliation.

On Thursday, the US claimed it had destroyed an Iranian drone, but this was disputed by Iranian officials.

US troops in Saudi Arabia

In response to the tensions with Iran, King Salman of Saudi Arabia has approved plans to host US troops to boost regional security, the SPA state news agency said late Friday.

The US deployment will eventually include more than 500 troops, as well as aircraft and air defense missiles, according to The Associated Press. Some troops have already arrived at Prince Sultan Air Base near the Saudi capital, Riyadh.

A spokesman for the Saudi Defense Ministry told SPA that the decision aims "to increase joint cooperation in defense of regional security and stability and preserve its peace."

The move had been in the works for several weeks and was not in response to the recent ship seizures. However, US President Donald Trump said Friday that US officials would talk with Britain about the seizure of the vessels.

"This only goes to show what I'm saying about Iran: Trouble, nothing but trouble," Trump said.

mm,dv/cmk (Reuters, AFP, dpa, AP)

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