Fed-up seafarers stranded in the Strait of Hormuz had an explicit message for US forces following its offer of safe passage amid repeated attacks on vessels from the Islamic Republic.

“F–k off,” one sailor was heard saying over marine radio, obtained by the Wall Street Journal, after the US military insisted the strait was open.

The US had radioed ships in the waterway to direct them toward the Omani section of the strait under its protection, as the American blockade on Iran’s ports took effect on Tuesday.

“US forces are prepared to maintain freedom of navigation and safeguard lawful commerce in accordance with international law,” the military said, according to the recording.

“The southern route of the strait remains open.”

The curt response then followed.

Despite America’s ongoing attacks on Iran’s military complex near the Strait of Hormuz, the Islamic republic has continued to fire warning shots and deadly strikes on ships that attempt to cross the Strait of Hormuz without its permission.

Of the 21 ships that crossed the strait on the first day of the blockade, none used the US-backed route near Oman, with 17 of the ships opting for Iran’s approved channel, according to maritime data firm Kpler.

One ship passed under a route approved by the International Maritime Organization, while the remaining three deployed shadow fleet tactics and sailed unseen through the strait.

Another 13 ships sailed through on Wednesday, with only a single ship, the Comoros-flagged Hero SD bulk carrier, traveling through the Omani route, according to Kpler.

Ten of the vessels, half of which are sanctioned due to their ties with Iran’s oil exports, traveled through the Tehran-approved route.

Maritime experts have previously warned that a majority of ships will not risk crossing the Strait of Hormuz under wartime conditions, especially so after Iran’s deadly attacks on vessels in recent days.

The US has said Iran had attacked seven commercial ships over the last week, leading to nearly a dozen crew members being killed, missing or injured.

But the US has proven some success in providing ships cover in the past, with more than 70 ships sneaking across the strait under American protection during the previous round of fighting.

That number, however, remains a drop in the bucket compared to the more than 130 ships that sailed through the oil choke point every day before the war.

Fully securing the Strait of Hormuz for safe travel would require far more military force and coordination than President Trump has been willing to deploy, Danny Citrinowicz, the former head of the Iran division of Israeli defense intelligence, said.

“The dilemma is quite simple: At the end of the day, if he wants to take control over the straits, he will need to take over the straits,” he told the WSJ. “He is not able to reach his military or strategic objectives with the force he has now.”

Brent crude oil remains stubbornly high above $84 per barrel on Thursday, about 22% higher than what it was a year ago.

The average price of gas in the US has also seen an uptick to $3.94 a gallon, about 10 cents higher than last week.