TEHRAN - Iran test-fired long range missiles on Saturday during a naval exercise in the Gulf, the semi-official Fars news agency said, following a threat by Tehran to close shipping lanes if the West imposes sanctions on its oil exports.

The 10-day naval drill in the Gulf began last week as Iran showed its resolve to counter any attack by enemies such as Israel or the United States.

"Iran test-fired missiles including long range (missiles), surface to sea, ... in the Persian Gulf," Fars said.

Tehran threatened on Tuesday to stop the flow of oil through the Strait of Hormuz in the Gulf if it became the target of an oil embargo over its nuclear ambitions, a move that could trigger military conflict with countries dependent on Gulf oil.

Tensions with the West have risen since the UN nuclear watchdog reported on November 8 that Iran appears to have worked on designing an atomic bomb and may still be pursuing research to that end.  

Iran denies this and says it needs nuclear technology to generate electricity to meet growing domestic demand.

During military drills in 2009, Iran test-fired its surface-to-surface Shahab-3 missile, said to be capable of reaching  Israel and U.S. bases in the Middle East.

Washington has expressed concern about Tehran's missiles, which include the Shahab-3 strategic intermediate range ballistic missile with a range of up to 1,000 km (625 miles), the Ghadr-1 with an estimated 1,600 km range and a Shahab-3 variant known as Sajjil-2 with a range of up to 2,400 km.

Iranian media have said the naval exercise differed from previous ones in terms of "the vastness of the area of action and the military equipment and tactics that are being employed".