The new head of Iran’s Supreme National Security Council on Sunday (September 6, 2026) said Tehran plans to announce an “exclusion zone” outside the Strait of Hormuz aimed at vessels it believes are attempting to transit the waterway.

Mohsen Rezaei’s comments to Iran’s state broadcaster came with few details, a day after the U.S. struck three Iranian oil tankers in response to Tehran launching ballistic missiles at U.S. warships.

Experts called the launches a dangerous escalation after Iran’s previous attacks at sea targeted commercial shipping.

The new zone should be announced in the coming days and weeks and “will begin from the line of the U.S. naval blockade, extend toward the Strait of Hormuz, and from this side continue into the Persian Gulf,” Mr. Rezaei said. “Any ship that enters this area with the intention of passing through the Strait of Hormuz and is identified will be placed on our sanctions list.” It is not clear where Iran defines the location of the weekslong U.S. blockade, which is aimed at Iranian ports and keeping Tehran from shipping out its oil. The U.S. military has said over 20 warships are supporting the blockade, which as of Sunday (September 6) had redirected 92 commercial ships and disabled three.

The U.S. has been introducing new measures to increase the economic pain on Iran after negotiations collapsed and no end to the intermittent fighting appears in sight.

Meanwhile, Iran continues to attack some ships trying to transit the strait, which has become an important source of leverage for Tehran in the war that began February 28 with U.S. and Israeli strikes.

In the negotiations that began on Saturday (April 11, 2026) in Pakistan, a key U.S. demand from Iran will be free passage—both unrestricted and cost-free—for merchant ships through the Strait of Hormuz. Although Iran has often threatened to control the strait and use it as leverage, including during the Iran-Iraq war, this is the first time the issue has been formally raised at the international negotiating table.

Iran has floated the idea of levying tolls to fund post-war reconstruction. However, tolls are typically charged only in artificial waterways such as the Suez Canal and Panama Canal—not in natural maritime chokepoints. Naturally occurring straits such as Malacca, Bosphorus and Dardanelles, Bab-el-Mandab, the Baltic Strait, and Gibraltar have traditionally allowed free passage.