Obama Says Option to Strike Iran Not a 'Bluff,' but Cites Repercussions.

WASHINGTON -- President Obama, speaking days before a crucial meeting with Prime Minister Benjamin Netanyahu of Israel, stiffened his pledge to prevent Iran from acquiring nuclear weapons, even as he warned Israel of the negative consequences of a pre-emptive military strike on Iran's nuclear facilities. Seeking to reassure a close American ally that contends it has reached a moment of reckoning with Iran, Mr. Obama rejected suggestions that the United States was willing to try to contain a nuclear-armed Iran. He declared explicitly that his administration would use force -- a ''military component,'' as he put it -- only as a last resort to prevent Tehran from acquiring a bomb. [ABSTRACT FROM PUBLISHER]