Israel is holding its largest-ever air force exercise this week with the participation of several countries including the United Arab Emirates, with whom it normalised ties last year. Amir Lazar, chief of Israeli air force operations, told reporters at the southern Ovda airbase the drills "don't focus on Iran", but army officials have said Iran remains Israel's top strategic threat and at the centre of much of its military planning. Israel has held the so-called "Blue Flag" exercises every two years since 2013 in the Negev desert to synchronise different types of aircraft, piloted by different countries to counter armed drones and other threats. With more than 70 fighter jets and some 1,500 personnel participating, this year's drills are the largest-ever held in Israel, Lazar said. Among the nations taking part are France, the United States and Germany, as well as the United Kingdom, whose aircraft flew over Israeli territory for the first time since the Jewish state's creation in 1948.