Iranian state television broadcast footage on Thursday of air defence units striking at a hypothetical enemy.
The broadcast is likely to be interpreted as a message to Israel and its allies to beware of attacking Iran.
Tehran denies accusations of warmongering and says there were routine exercises.
Iranian Defence Minister Ahmad Vahidi said: “The Islamic Republic has never asked for or entered a war.
“But it has long been said that in case of an attack initiated by our enemies, we will strongly defend ourselves.”
Israel is said to be planning an attack on Iran’s nuclear sites amid Western fears that its atomic programme has military dimensions.
Israeli Finance Minister Yuval Steinitz told the CNBC news channel that Iran will be able to strike US soil by 2015.
“They are working now and they are investing a lot of billions of dollars in order to develop intercontinental ballistic missiles,” Steinitz said.
“We estimate that in two to three years they will have their first intercontinental ballistic missiles that can reach the east coast of America.”
Iran rejects Western fears it is planning to acquire a nuclear weapon and says its programme is only for civilian use.
The heightened tensions come as the country prepares for its first elections since a 2009 presidential poll that sparked mass protests.
A total of 344 vetted candidates are vying for 290 seats in parliament.
Reformist groups are boycotting the vote in protest at a state-led crackdown on political expression in the past three years since President Mahmoud Ahmadinejad’s re-election.