No oil will be permitted to pass through the key oil transit Strait of Hormuz if the West applies sanctions on Iran's oil exports, Iranian Vice-President Mohammad Reza Rahimi warned.
The threat was reported by the state news agency IRNA as Iran conducted navy wargames near the Strait of Hormuz, at the entrance of the oil-rich Gulf.
The threat underlined Iran's readiness to target the narrow stretch of water along its Gulf coast if it is attacked or economically strangled by Western sanctions.
More than a third of the world's tanker-borne oil passes through the Strait of Hormuz.
The US maintains a navy presence in the Gulf in large part to ensure that passage remains free.
Iran is currently carrying out navy exercises in international waters to the east of the Strait of Hormuz.
Although Iranian wargames occur periodically, the timing of these is seen as a show of strength as the US and Europe prepare to impose further sanctions on Iran's oil and financial sectors.
The last round of sanctions, announced in November, triggered a pro-regime protest in front of the British embassy in Tehran during which Basij militia members overran the mission, ransacking it.
