Iran has rejected a U.S. warning against blocking oil shipments through the strategic Strait of Hormuz, as a war of words between the two countries continues.

Iran's semi-official Fars news agency Thursday quoted Revolutionary Guard commander Hossein Salami as saying Iran can carry out its own “defensive strategies.”

Tehran threatened earlier this week to block the entrance to the Persian Gulf if the West imposes sanctions targeting Iran's oil exports. Such a move by the West would add to several rounds of sanctions already imposed on Iran over its controversial nuclear program.

More than one-third of the world's tanker-borne oil supply passes through the Strait of Hormuz. A closure could temporarily cut off some oil supplies and impact the price of oil worldwide.

The Pentagon has said interfering with the passage of vessels through the strait will not be tolerated.

A recent United Nations report said Iran appears to be secretly working on designing a nuclear weapon — something Tehran denies. European Union ministers have said that a decision on further economic sanctions — including a boycott of Iranian oil — will be made in the coming weeks. The vast majority of Iran's foreign revenue comes from oil exports.

Separately, a spokeswoman for the Bahrain-based U.S. Fifth Fleet told VOA in an email that the flow of goods through the strait is “vital to regional and global prosperity.” Lieutenant Rebecca Rebarich said the U.S. Navy is ready to “counter malevolent actions” to ensure navigation freedom.

Iranian Vice President Mohammad Reza Rahimi said Tuesday that if Iranian oil is banned, “then not a drop of oil will pass through the Strait of Hormuz.”

Iran's warnings come as its naval forces continue a 10-day exercise in the strait and nearby waters that began on Saturday.

The Associated Press quoted a Saudi oil ministry official as saying Gulf oil producers would be ready to step in, if necessary, to make up for any losses of Iranian crude.