The head of Iran's Supreme National Security Council, Mohsen Rezaei, said on Sunday that Tehran plans to announce an "exclusion zone" outside the Strait of Hormuz aimed at vessels it believes are attempting to transit the waterway. He offered few details in remarks to Iran's state broadcaster, according to the report.

Rezaei's comments followed a day after the U.S. struck three Iranian oil tankers in response to Iran launching ballistic missiles at U.S. warships. Experts described the missile launches as a dangerous escalation after Iran's previous attacks at sea targeted commercial shipping.

Rezaei said the 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." His quoted remarks continued, but the available account did not include the rest of the sentence.

The U.S. has been introducing new measures to increase economic pressure on Iran after negotiations collapsed, and no end to the intermittent fighting appears in sight, the report said. Sources provided no further details on the planned exclusion zone or its enforcement.