As the war in Iran enters its ninth week with no clear end in sight, shipping traffic in the Persian Gulf and the Strait of Hormuz has been completely reshaped, heavily disrupting global markets and supply chains for oil, natural gas, fertilizer and other essential products.
Before the United States and Israel launched their attacks on Iran in late February about 3,000 vessels typically passed through the Strait of Hormuz each month, according to Lloyd’s List Intelligence. Oil tankers passing through accounted for an estimated 15 million barrels per day of crude and other oil product exports, data from the analytics firm Kpler shows, amounting to about one-fifth of the world’s oil trade.
But since the war began, traffic has been reduced to a trickle, with just 154 vessels recorded crossing in the entire month of March, according to Kpler data.
“The disruption is both rapid and unprecedented,” said Dimitris Ampatzidis, a maritime risk and compliance manager at Kpler.
Overall, traffic through Hormuz in the last two months has run at about 5% of the pre-war average, leading to shortages of refined products, especially in Asia.
Despite the dramatic disruption, a small number of ships are still coming in and out of the Persian Gulf via the strait. But experts say more vessels are leaving than entering, indicating that shipping operators are mitigating risks by avoiding the area entirely and reallocating flows.
“There are still over 800 vessels in the gulf, but ‘stranded’ isn’t the right term for all of them,” Ampatzidis told CNN in an email. “Many regional vessels, particularly Iranian and gulf operators, are continuing to operate normally within local routes.”
The strait is about 24 miles across at its narrowest point, which creates a chokepoint that Iran has been able to exploit as it exerts increased control over the world’s shipping and threaten vessels without needing to patrol a large area.
Following a ceasefire agreed on April 8, Iranian Foreign Minister Abbas Araghchi initially said that safe passage through the Strait of Hormuz would be possible via coordination with Iranian authorities. But the next day, Iran’s Islamic Revolutionary Guard Corps (IRGC) claimed that traffic through the strait had been halted again, following what it said was an Israeli ceasefire violation in Lebanon .
The IRGC has since published a map showing what it called “alternative routes for transit” through the Strait of Hormuz that channel traffic through Iran’s territorial waters and past Larak Island, enabling checks by the Iranian navy and port authorities. The Revolutionary Guard also marked a so-called “danger zone” in the part of the strait that was previously the main International Maritime Organization (IMO) shipping corridor.
“The official IMO lane has been almost entirely abandoned. Instead, most vessels are now using a route along the Iranian coastline,” Ampatzidis said. “At the same time, a significant share of traffic remains ‘dark,’ meaning vessels are operating outside any verifiable corridor.”
Meanwhile, Iranian state media has reported on the country’s plans to continue charging transit fees to some ships seeking to pass, making it lucrative for Iran to try to retain control of the waterway.
As a response to Iran’s actions, the US on April 13 announced a blockade on ships entering or exiting Iranian ports and coastal areas. US forces have directed at least 38 vessels to turn around or return to an Iranian port since that blockade began, according to US Central Command .
Still, the latest shipping data shows that most vessels that have transited the Strait of Hormuz in recent days have taken the route designated by Iranian authorities, and about half of them loaded their cargoes at Iranian ports in defiance of the US blockade.
Iran’s ports are typically far from the busiest in the Persian Gulf, and the ports of Saudi Arabia and the United Arab Emirates usually have much higher traffic. But those countries and other gulf allies have been forced to cut production amid the shipping disruptions and threats from Iran.
Importing countries, particularly in Asia, are also suffering as they face fuel shortages .
“Japan and South Korea were big importers of Saudi and Middle Eastern crudes. And you know, looking at the rest of Asia — taking out China — we can see the big impact and the loss in terms of imports,” said Ioannis Papadimitriou, lead freight analyst at the data firm Vortexa.
Papadimitriou noted that the whole shipping industry is trying to drum up exports from alternative regions to keep oil moving and, crucially, to stay employed.
“If the situation is prolonged, we’re going to see loss of barrels that cannot be replaced from anywhere,” the Vortexa analyst added. “This is where we could see the real loss of cargoes — really hitting the shipping industry and dropping the (freight) rates.”
CNN’s Tim Lister, Eleni Giokos and Agne Jurkenaite contributed to this report.
