US: Difficult work remains on Iran nuke talks
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Negotiations over Iran's nuclear program grew frantic on Saturday amid signs of discord, with the French and German foreign ministers joining US Secretary of State John Kerry in talks with Tehran's top diplomat ahead of an end-of-March deadline for a preliminary deal.
The US State Department said "serious but difficult work" remained for negotiators, with the pace of discussions expected to intensify as "we assess if an understanding is possible."
