A U.S.-Israeli joint defense drill designed to counter ballistic missile threats from Iran, Hezbollah, Syria and Gaza began Wednesday, Israeli officials said.

The exercise is the largest ever to take place on Israeli soil and will deal with a number of scenarios, Maariv said.

More than 1,000 Israeli soldiers and 1,000 members of the U.S. military European Command will participate in the exercise, dubbed Juniper Cobra, that began Wednesday and runs through Nov.5, the Israeli army said in a statement released Tuesday.

The army said it is the fifth series of biennial exercises conducted by the two countries to integrate missile and air defense systems.

During the two week drill, a number of U.S. forces will be deployed to a number of sites in Israel, the army said.

While the army stressed the exercise is not in response to any world events, Israel Radio Wednesday quoted an unnamed Israeli military official saying the extensive drill is in preparation for a face off with Iran.

Last month, Chief of General Staff Lt. Gen. Gabi Ashkenazi said while sanctions are the best option to deal with the Iranian nuclear threat, Israel has the right to defend itself.

In recent weeks, 17 American warships and transport planes loaded with air defense systems arrived in Israel ahead of the drill.