Iran uses 'selective passage' to control Strait of Hormuz shipping

Iran is using a system of "selective passage" to control shipping through the Strait of Hormuz, effectively deciding which vessels are allowed to pass as the US and Israel's war on the country disrupts global energy flows.

While Washington has sought to assemble an international naval coalition to reopen the strategic waterway, shipping activity on the ground suggests a different reality.

The strait has not been fully closed, but transit is no longer treated as a guaranteed maritime right. Instead, it has become a negotiable privilege granted by Tehran on a case-by-case basis.

Iran is effectively regulating traffic through undeclared transit approvals, with vessels required to secure informal clearance to pass through, The New Arab can report.

The shift marks a departure from the strait’s traditional status as an open international shipping lane, with the impact of Iranian attacks on shipping severely impacting global trade.

Data from maritime publication Lloyd’s List shows that tanker traffic through Hormuz has collapsed by more than 90 percent in March, falling from a pre-war average of 50 to 70 oil and gas tankers per day to fewer than 10. In some cases, days have passed with almost no vessels transiting the route.

Around 1,100 ships are now reported to be waiting in Gulf waters, including roughly 250 oil tankers, as uncertainty and security risks deter commercial operators. Shipping companies and insurers have largely avoided the area, further contributing to the sharp decline in traffic.

At the same time, Iran has not imposed a total blockade on the Gulf and instead appears to be allowing limited, controlled movement through the strait.

A Pakistani-flagged oil tanker, KARACHI, was tracked sailing through the Strait of Hormuz into the Gulf of Oman this week, becoming one of the first non-Iranian vessels to make a visible crossing since the war began.

Analysts say the transit suggests Iran is permitting certain shipments through “safe” corridors negotiated informally, particularly for countries not directly involved in the conflict.

Iranian Foreign Minister Abbas Araghchi has previously said the strait is "open" but "closed only to our enemies", reflecting a policy of selective access.

Some vessels have also adopted what analysts describe as "dark transit" tactics, switching off tracking systems while passing through the strait. These movements are often associated with the so-called "shadow fleet" - ships operating outside formal regulatory frameworks that have continued to move oil despite the disruption.

The selective approach allows Iran to exert pressure on global energy markets without triggering the full consequences of a complete shutdown.

The Strait of Hormuz normally carries around one-fifth of the world’s oil and a significant share of liquefied natural gas exports, making it one of the most critical chokepoints in global trade.

As flows through Hormuz have severely declined, Gulf producers have begun shifting exports to alternative routes. According to the International Energy Agency, Saudi Arabia has increased shipments through its East-West pipeline to the Red Sea, while the UAE is boosting flows via the Habshan-Fujairah pipeline, which bypasses the strait entirely.

Despite these efforts, the disruption has pushed oil prices sharply higher and increased volatility in global markets.

Analysts warn that even limited interference with shipping in Hormuz could have outsized effects on supply, particularly if attacks on vessels or infrastructure intensify.

The current situation suggests that the strait is no longer functioning as a neutral international passage, but as a strategic tool in a wider conflict.