Kerry asserts obstacles to Iran nuke pact mostly 'political'
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WASHINGTON - US Secretary of State John Kerry, returning to talks with Iran on its nuclear program, says most of the differences still barring an agreement are political rather than technical.
Kerry, who is to sit down Sunday in Switzerland with Iranian Foreign Minister Mohammed Javad Zarif, tells CBS News that Tehran must fulfill "the promise of proving to the world" that its nuclear program is peaceful.
