Iranian President Hassan Rouhani on Tuesday repeated his threat to close the Strait of Hormuz, the passageway for nearly a third of all oil traded by sea, if the US shuts off Iran's oil exports.
State TV quoted Rouhani as saying that "if someday, the United States decides to block Iran's oil (exports), no oil will be exported from the Persian Gulf."
The strait at the mouth of the Persian Gulf is crucial to global energy supplies.
Rouhani also pledged that the United States would not be able to prevent Iran from exporting its crude.
Rouhani has made similar threats in the months since US President Donald Trump withdrew the US from the 2015 nuclear deal and began restoring sanctions. Trump has vowed to eventually cut off all Iranian oil exports, but the administration has given waivers to several countries.