Iran has launched a major military exercise to prepare for possible attacks on its nuclear installations.

The exercise, which will last five days and cover one-third of Iran's territory, will focus on defence against air raids and reconnaissance flights. Iranian state-controlled media report the exercise is the largest ever held in the country's history.

Iran is under great international pressure to give up its nuclear programme. Europe, Israel and the United States accuse Iran of secretly developing nuclear weapons. However, Tehran insists the programme is exclusively intended for the generation of nuclear power.

A senior Iranian officer has warned that an Israeli air strike would lead to a retaliatory missile strike on Tel Aviv. 

Photo: Iranian nuclear reactor (EPA)