Mohsen Rezaei, secretary of Iran's Supreme National Security Council, warned on Monday that Tehran would respond to what it calls US "economic warfare" by imposing a maritime exclusion zone across the Persian Gulf.
He additionally said the country's military posture toward American forces had been "fundamentally recalibrated."
"In recent days, Washington has received a clear warning from Iran's new missiles," Rezaei said in a post on X.
"Economic warfare will be met by a maritime exclusion zone across the Persian Gulf to the blockade perimeter," he added, saying the zone would extend to the edge of the US naval blockade currently in place around Iranian ports.
Rezaei said the shift meant Iran's forces were now postured differently against American assets in the region. "The operational posture toward US warships and bases has been fundamentally recalibrated," he said.
The warning builds on an announcement Rezaei made on 6 September, when he said Tehran would establish the exclusion zone along with a new shipping corridor through the Strait of Hormuz within days, Reuters reported at the time.
ALSO READ: 'America Started The War But...': Amid Hormuz Tensions, Iran To Announce Restricted Zone Near Strait
The threat comes as Washington moves to tighten pressure on Tehran, including at the United Nations, over Iran's nuclear programme.
The US Central Command said on Sunday that American forces enforcing the naval blockade against Iranian ports had redirected 92 commercial vessels. Shipping traffic through the Strait of Hormuz has meanwhile fallen to its lowest levels since May.
The exchange is the latest flashpoint in a confrontation that began on 28 February, when US and Israeli strikes on Iran triggered a broader war and prompted Tehran to shut the Strait of Hormuz to shipping. Washington responded in April with a naval blockade of Iranian ports, cutting off tanker traffic and disrupting roughly a fifth of the world's seaborne oil and gas trade that normally passes through the waterway.
Rezaei's comments follow other signs of rising tension in the Gulf this week, including Iranian criticism of Western allies over their continued backing of US and Israeli actions.
ALSO READ: Iran, US Trade Tanker Attacks As Six-Month War Escalates
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