Iran nuclear talks: Obama says he's willing to 'walk away'

U.S. President Barack Obama says he is still willing to "walk away" from a nuclear deal with Iran if it does not meet his goal of blocking Tehran's paths to a nuclear weapon.

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Obama's comments come shortly after diplomats announced that talks will be extended beyond a Tuesday night deadline.

The president says a framework agreement reached earlier this year would meet his goals. He emphasized the need for Iran to allow inspectors into nuclear sites and verify it is living up to its commitments.

Negotiators in Vienna hope to clinch an accord curbing Iran's nuclear program for a decade in exchange for tens of billions of dollars in relief from economic sanctions.

Disagreements persist, however, including over the level of inspections and how quickly the West will roll back sanctions.