Iranian state TV says america has added three much more domestically-built submarines to it is naval fleet.
The Sunday report mentioned the vessels were transported to the Iranian navy around southern port of Bandar Abbas. It said the submarines were through the Ghadir class, of which Iran already has four.
This class of submarine could fire missiles and torpedoes and operate while in the Gulf's shallow waters.
The move is seen included in Iran's effort to update its defense capabilities anywhere between escalating tension over it has the nuclear program. The Western suspects Iran is looking at developing nuclear weaponry, a charge Iran denies.