Israeli Defense Forces Lt. Gen. Gabi Ashkenazi and Chairman of the Joint Chiefs of Staff Adm. Mike Mullen, U.S. Navy, wave to onlookers at the Yad Vashem Holocaust Memorial Museum in Jerusalem on Feb. 15, 2010. Photo: U.S. Navy.

The United States and Israel are scheduled to hold its largest-ever joint defense exercise in Israel on Oct. 21.

Dubbed the Austere Challenge 12 (AC12), the exercise was originally scheduled for last spring but was postponed over regional tensions with Iran. While the Iran threat continues, an IDF spokesman told the Jerusalem Post that the drill was “unrelated to any pinpoint developments in the region.”

The three-week air defense exercise will test cooperation between the militaries by simulating various missile defense scenarios, and is expected to end with a live-fire interception of a decoy incoming Patriot missile.