National security

Iran bought the two-seat, twin-engine jet, also called the Tomcat and made famous in the 1986 movie Top Gun, in the 1970s when it was a US ally.

Dawn Dearden, spokeswoman for the agency, said the Pentagon planned to destroy about 10,000 components unique to the F-14 and was reviewing what to do with 23,000 parts that could be used for other aircraft.

Ron Wyden, Democrat senator for Oregon and member of the Senate intelligence committee, has written legislation to eliminate all Pentagon sales of F-14 parts.

Wyden said: "I'm glad that the Pentagon is shutting the door on these weapons sales. National security, however, demands that we lock it.

"The only way to ensure that America doesn't arm Iran is for the US to permanently stop selling these weapons parts."

Wyden's bill would also ban previous buyers of surplus F-14 parts from exporting them to third parties.

The government accountability office has issued several reports in recent years raising concerns about the lack of adequate security in the Pentagon's property sales.

The office's undercover investigators found several sensitive excess items, including 12 digital microcircuits used in F-14s, were improperly sold to the public.

Drift to war

In a separate development, Republican and Democratic senators have warned against a drift towards war with Iran and suggested the US was missing a chance to engage the country in potentially helpful talks over its neighbour Iraq.

Barack Obama, Democrat senator for Illinois, told a senate foreign relations committee on Tuesday that: "What I think many of us are concerned about is that we stumble into active hostilities with Iran without having aggressively pursued diplomatic approaches, without the American people understanding exactly what's taking place."

Obama, a candidate for president in 2008, warned that senators of both parties will demand "clarity and transparency in terms of US policy so that we don't repeat some of the mistakes that have been made in the past".

This appeared to be a reference to the faulty intelligence underlying the US invasion of Iraq.

During the hearing, Chuck Hagel, Republican senator for Nebraska, asked John Negroponte, the US director of intelligence, if he thought the US was edging towards a military confrontation with Tehran.

In response, Negroponte stated a preference for diplomacy, although he later added "we don't rule out other possibilities".

Also on Tuesday, William Fallon, the navy admiral poised to lead US forces in the Middle East, said Iran wanted to limit America's influence in the region.

Fallon told the senate armed services committee: "They have not been helpful in Iraq. It seems to me that in the region, as they grow their military capabilities, we're going to have to pay close attention to what they do and what they may bring to the table.

George Bush, the US president, said on Tuesday that the US "will deal with it" if Iran escalates military action inside Iraq and endangers American forces.