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Iran nuclear talks in Istanbul 'constructive'
The first discussions between Iran and six world powers on Tehran's nuclear programme have ended on a positive note, Western officials have said.
But some diplomats said there was still a long way to go, and specific actions were needed from Iran.
The talks in Istanbul on Saturday were the first for 15 months. The next round will take place in Baghdad on 23 May.
Iran says its programme is peaceful, but critics suspect it of seeking to develop a nuclear weapons programme.
The European Union's foreign policy chief, Catherine Ashton, described the talks as "constructive and useful".