Iran and six world powers were not able to bridge their different positions on Tehran's nuclear programme, EU foreign policy chief Catherine Ashton said Tuesday at the end of two days of talks in Moscow, DPA reported.
Working groups of both sides were scheduled to meet in Istanbul on July 3, said Ashton, who led the grouping of the United States, Britain, France, Germany, Russia and China.
A new full round of talks would depend on the outcome of the working group meeting.
Ashton said that big differences remained between the two sides.