The US military has helped pass 660 million barrels of oil through Hormuz since May

The US military has helped tankers transport more than 660 million barrels of crude oil through the Strait of Hormuz since early May, Central Command told CNBC this week.

The military has helped about 1,300 commercial ships navigate through Hormuz during the same period, U.S. Navy Capt. Tim Hawkins, a spokesman for Central Command, said in a statement Thursday.

“Multiple routes remain clear and open to commercial traffic,” Hawkins said.

This suggests that at least 160 million barrels, or more than 7 million barrels per day, have transited the strait over the past three weeks, according to previous military statements. Central Command said on July 29 that US forces had helped 500 million barrels through Hormuz since May.

Shipments are still far below pre-war fuel exports, when around 20 million bpd of crude oil and products passed through Hormuz. But US military figures indicate that a substantial amount of oil is passing through the strait despite Iranian threats and attacks.

It is unclear exactly how much oil leaves Hormuz daily, as the US government has provided different estimates that are often higher than data from independent ship tracking companies.

US officials told Axios on Wednesday that around 10 million bpd have left the strait in recent weeks. Energy Secretary Chris Wright said on August 11 that the seven-day average had risen to nearly 9 million bpd.

Private observers give other estimates.

Maritime intelligence firm Windward estimates that crude oil exports through Hormuz averaged around 5 million bpd in July, compared with around 4 million bpd in June and 1.6 million bpd in May.

Exports in August are also expected to increase from July, said Michelle Wiese Bockmann, senior maritime intelligence analyst at Windward.

“My assessment is that it is increasing and it is increasing rapidly even though Iran is putting enormous pressure on maritime security,” Bockmann said.

“The Gulf States have American military protection; that is no secret,” the analyst said. They are “willing to do everything they can” to boost oil exports, he said.

There is a lack of solid information on exactly how much oil moves through Hormuz because of the complexity of tracking ships during the war, said Bridget Diakun, director of maritime research and intelligence at Lloyd’s List.

Ships typically transit at night, but satellite images are usually taken in the morning, Diakun said. “There are a lot of unknowns,” he said at a briefing Thursday.

The US energy secretary said last week that “many private companies underestimate the number of ships leaving the Strait of Hormuz because ships move covertly through the waterway.”

“In coordination with the U.S. military, the U.S. Department of Energy maintains the best available data related to oil and petroleum products leaving the Arabian Gulf,” Wright said in a social media post.

Challenged control

The security situation in Hormuz remains controversial. Iran said on Tuesday it closed Hormuz until the United States meets its obligations under the interim peace deal signed on June 17. Meanwhile, President Donald Trump has insisted that the strait is open and under American control.

Hormuz has been divided between two different sea routes for months. The US military assists ships using the southern route along the coast of Oman. It has also imposed a naval blockade against Iranian ports. Tehran demands that ships use a northern route through its territorial waters or risk being attacked.

“It is a controversial security situation in the Strait of Hormuz,” said Jakob Larsen, chief security officer at BIMCO, one of the world’s largest shipping trade associations.

The strait is 21 miles wide at its narrowest point. The United States has more control closer to Oman and Iran has more control closer to its coast, Larsen said.

“But both sides are still capable of projecting power across the strait,” he said. “It is not really possible for either party to fully defend its own interests in the waters of its own territory.”

At least 17 commercial ships were attacked in and around the strait in July and August, according to the International Maritime Organization, a United Nations agency. At least four sailors were killed in those attacks and more than a dozen were wounded.

But the tankers who make the trip earn $500,000 a day, said Bockmann, the Windward analyst. Seafarers receive double or triple their salary for making these transits, he said.

“It’s a very intense and serious operation to get the oil out: high risk, high gain,” Bockmann said.