The attack, which can take place already before the presidential election in the USA on Tuesday next week, is expected to be carried out with the help of a large number of drones and ballistic missiles.
Using pro-Iranian militias in Iraq to carry out the attack may be an attempt to prevent Israel from retaliating by attacking strategic targets in Iran.
On Thursday, Iran warned of a "hard and regrettable" response to the deadly Israeli attack on Saturday against Iranian military installations, reported the AFP news agency, citing local media.
Last week, Israel carried out three major attacks against Iran and hit several military targets – a revenge for the Iranian attack on Israel on October 1, Israel claimed at the time.