Iran has successfully tested what it described as a "flying boat," state television has reported.

This is the latest in a series of domestically produced weapons that Tehran has tested during a three-day military exercise in the Gulf.

"A super-modern flying boat was successfully tested in the 'Great Prophet' wargame in Persian Gulf waters," state television said.

State-run radio also reported that Iran had also tested its Kowsar missile - a land-to-sea missile designed to sink ships in the Gulf.

Iran has said it has already tested a radar-evading rocket and the Hoot (whale) underwater missile which could outpace any enemy warship during the maneouvres.

Exaggeration

The US has expressed concern at the military exercises, but believes that Tehran is likely to be exaggerating its weapons capabilities.

"We know that the Iranians are always trying to improve their weapons system by both foreign and indigenous measures," said Brian Whitman, a Pentagon spokesman.

"It's possible that they are increasing their capability and making strides in radar absorbing materials and technology."

But he added that "the Iranians have also been known to boast and exaggerate their statements about greater technical and tactical capabilities."

Domestic Production

Russian military analysts have said it was unlikely that the Hoot torpedoes were Iranian-built, and judging by the fuzzy television pictures showing the tests, said they appeared very similar to the Russian-made VA-111 Shkval, the world's fastest known underwater missile.

Ruslan Pukhov, an expert with the Center for Analysis of Strategies and Technologies, said it was possible that Iran could have obtained Shkvals through the Chinese - who bought some of the missiles from the former Soviet republic of Kyrgyzstan in the mid-1990's.

More than 17,000 Iranian Revolutionary Guards troops, along with some 1500 warships, boats and aircraft are taking part in the week-long maneouvres in the Gulf.

After decades of relying on foreign purchases, Iran's military has been working to boost its domestic production of weapons.

Since 1992, Iran has produced its own tanks, armoured personnel carriers, missiles and a fighter plane. It announced in early 2005 that it had begun production of torpedoes.

PHOTO CAPTION

A video frame grab of a light-green light aircraft skimming along the water in Iran, April 4, 2006. (REUTERS)