Explainer: What are the Iran nuclear talks all about?

Negotiations to bring the United States back into a landmark nuclear deal with Iran resumed Thursday in Vienna amid signs of progress - but also under the shadow of an attack this week on Iran's main nuclear facility. After more than two hours of talks characterized by Russia's delegate as generally positive, issues were turned back over to two working groups for continued discussion and refinement.

Explainer: What are the Iran nuclear talks all about?
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Negotiations to bring the United States back into a landmark nuclear deal with Iran resumed Thursday in Vienna amid signs of progress - but also under the shadow of an attack this week on Iran's main nuclear facility. After more than two hours of talks characterized by Russia's delegate as generally positive, issues were turned back over to two working groups for continued discussion and refinement.