Foreign powers negotiating with Tehran on its nuclear programme say they are “disappointed” after a round of talks ended without progress in Istanbul.
EU foreign policy chief Baroness Ashton, who led the international team, said Iran had sought to impose pre-conditions on any agreement.
While no date was set for new talks, she said the “door remained open”.
An Iranian official told Reuters there would be further talks but no decision had been taken on the date or venue.
The international team had proposed a new version of a nuclear fuel swap, but Iran sought to discuss disarmament.
Western diplomatic sources have spoken of anger and frustration over Iran’s behaviour at the talks.
Baroness Ashton led a delegation from France
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