German Foreign Minister Frank Walter Steinmeier (2nd-L), US Secretary of Energy Ernest Moniz (C-L), US Secretary of State John Kerry (C), US Under Secretary for Political Affairs Wendy Sherman (C-R), and French Foreign Minister Laurent Fabius (R)
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Growing optimism for Iran nuclear talks

There is growing optimism that an agreement can be reached on Iran's nuclear programme ahead of Tuesday's deadline, although some critical sticking points remain.

Negotiators have started arriving in the Swiss city of Lausanne for the final days of talks.

Barbara Plett Usher reports.