Iran has developed a 900kg "smart bomb", official media quoted a Defence Ministry statement as saying, in the latest announcement from Tehran about progress regarding military hardware.
The guided bomb, named Qased (Messenger), was developed by specialists within the ministry and is now operational, IRNA news agency said, adding it could be dropped from F-4 and F-5 jets.
Iran still uses planes, such as the F-5, supplied by the United States to the government of the former shah of Iran, who was a close US ally. Mohammad Reza Shah was ousted in the 1979 Islamic revolution, after which Washington cut ties with Tehran.
The two countries are embroiled in a deepening standoff over Iran's nuclear programme, which the West suspects is aimed at making atom bombs, a charge Iran denies.
Iran often says it has built new arms or upgraded weapons but rarely gives enough details for analysts to determine their capabilities. Although much of Iran's weaponry is outmoded, analysts say Iran has become proficient at modifying such arms.
Defence Minister Mostafa Mohammad Najjar said last year Iran had designed the Qased bomb but that it had yet to be tested. He said only a limited number of countries possessed the technology of "smart and guided weaponry".
The United States says it would prefer a diplomatic solution to the nuclear row, but has not ruled out military action. Iran has threatened to hit back at US regional interests if attacked.