The U.S. military is considering putting armed personnel on commercial ships traveling through the Strait of Hormuz, in what would be an unheard of action aimed at stopping Iran from seizing and harassing civilian vessels, American officials told The Associated Press on Thursday.

Since 2019, Iran has seized a series of ships in the strait, the narrow mouth of the Persian Gulf, as part of its efforts to pressure the West over negotiations regarding its collapsed nuclear deal with world powers. Putting U.S. troops on commercial ships could further deter Iran from seizing vessels — or escalate tensions further.

The contemplated move also would represent an extraordinary commitment in the Mideast by U.S. forces as the Pentagon tries to focus on Russia and China. America didn't even take the step during the so-called "Tanker War," which culminated with the U.S. Navy and Iran fighting a one-day naval battle in 1988 that was the Navy's largest since World War II.

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While officials offered few details of the plan, it comes as thousands of Marines and sailors on both the amphibious assault ship USS Bataan and the USS Carter Hall, a landing ship, are on their way to the Persian Gulf. Those Marines and sailors could provide the backbone for any armed guard mission in the strait, through which 20% of the world's crude oil passes.

Iran's mission to the United Nations did not respond to a request for comment from AP about the U.S. proposal. Hours later, however, Iran's state-run IRNA news agency acknowledged the proposal, citing this AP report.

Five U.S. officials, who spoke on condition of anonymity to discuss the proposal, acknowledged its broad details. The officials stressed no final decision had been made and that discussions continue between U.S. military officials and America's Gulf Arab allies in the region.

Officials said the Marines and Navy sailors would provide the security only at the request of the ships involved. One official described the process as complex, saying any deployment likely also would require approval of the country under which the ship is flagged and the country under which the owner is registered. So far, that has yet to happen and it might not for some time, the official said.

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At the Pentagon, Brig. Gen. Pat Ryder was asked about the plans and would only say that he has no announcements to make on the matter. More broadly, however, he noted that additional ships, aircraft and Marines have been deployed to the Gulf region, making it easier to respond more quickly to any Iranian provocations.

That effort by U.S. and partners, he said, is aimed at ensuring "the Strait of Hormuz remains open, there's freedom of navigation, and that we're deterring any type of malign activity."

And White House National Security Council spokesman John Kirby, speaking to reporters, underscored the importance of the strait and U.S. concerns about Iranian harassment of vessels there.

"The Strait of Hormuz is a vital seaway that has a huge impact on seaborne trade around the world," Kirby said. "It's a critical chokepoint in the maritime world. And we have seen threats by Iran to affect that chokepoint."

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Earlier Thursday, Vice Adm. Brad Cooper, the head of the Navy's Mideast-based 5th Fleet, met with the head of the Gulf Cooperation Council. The six-nation bloc includes Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates.

While a statement from the GCC about the meeting did not hint at the proposal, it did say that Cooper and officials discussed "strengthening GCC-U.S. cooperation and working with international and regional partners."

The Bataan and Carter Hall left Norfolk, Virginia, on July 10 on a mission the Pentagon described as being "in response to recent attempts by Iran to threaten the free flow of commerce in the Strait of Hormuz and its surrounding waters." The ships made a port visit earlier this week at Souda Bay, Greece, drawing closer to the Mideast, according to photographs released by the Navy.

Already, the U.S. has sent A-10 Thunderbolt II warplanes, F-16 and F-35 fighters, as well as the destroyer USS Thomas Hudner, and other warships to the region over Iran's actions at sea.

The deployment has captured Iran's attention, with its chief diplomat telling neighboring nations that the region doesn't need "foreigners" providing security. On Wednesday, Iran's paramilitary Revolutionary Guard launched a surprise military drill on disputed islands in the Persian Gulf, with swarms of small fast boats, paratroopers and missile units taking part.

The renewed hostilities come as Iran now enriches uranium closer than ever to weapons-grade levels after the collapse of its 2015 nuclear deal. International inspectors also believe it has enough enriched uranium for "several" nuclear bombs if it chose to build them. Iran maintains its program is for peaceful purposes, and U.S. intelligence agencies assess Tehran is not pursuing an atomic bomb.

The U.S. also has pursued ships across the world believed to be carrying sanctioned Iranian oil. Oil industry worries over another seizure by Iran likely has left a ship allegedly carrying Iranian oil stranded off Texas as no company has yet to unload it.