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The Chairman of the Joint Chiefs of Staff says the US has a plan in place to attack Iran, if necessary.
Mike Mullen says military actions have been on the table and remain on the table for curbing Iran's nuclear ambition. But he says he hopes it doesn't come to that.
Washington's preferred option remains a combination of multilateral diplomacy and international sanctions.
Iran's president Mahmoud Ahmadinejad says the nation's Army has made strong response plans, in case of any possible US or Israeli attack.