US Defence Secretary Leon Panetta has warned that Iran must either negotiate acceptable limits on its nuclear programme or face the possibility of US military action to stop it from getting the bomb.
Panetta made his remarks Wednesday outside a city in southern Israel, with an "Iron Dome" anti-rocket defence system as a backdrop.
Panetta said repeatedly that "all options", including military force, are on the table to stop Iran, should sanctions and diplomacy, the preferred means of persuasion, ultimately fail.
Israeli Defence Minister Ehud Barak, standing beside Panetta, said he sees an "extremely low" probability that sanctions will ever compel Iran to give up its nuclear activities. Panetta arrived in Israel on Tuesday after meeting in Cairo with Egypt's new president and its military chief.
Speaking before the talks, Panetta said Wednesday's discussion with Prime Minister Binyamin Netanyahu and Defence Minister Ehud Barak will be "more about what is the threat we are confronting" in Iran's nuclear programme and about sharing intelligence information.
In Cairo, Panetta denied Israeli press reports that he planned to share with the Israelis any US plans for military action against Iran. Iran says its nuclear work is for civilian energy uses, but suspicions that the Islamic republic will use enriched uranium for nuclear weapons has resulted in international sanctions and sabre-rattling from Israel, which perceives a nuclear Iran as an existential threat.
The United States has discouraged Israel from a unilateral, pre-emptive military strike on Iran, but has said it would keep all options available.
"What we are discussing are various contingencies and how we would respond," Panetta said. Asked whether any such contingencies include plans for potential military action against Iran, he said, "We obviously continue to work on a number of options in that area."