The next round of nuclear negotiations are getting under way on July 24 between Iran and the so-called P5+1 group, comprising the permanent United Nations Security Council members plus Germany.
The meeting, at the deputy negotiator level, was expected to discuss the possibility of restarting high-level talks.
Previous rounds of talks have collapsed over Western demands that Iran halt uranium enrichment.
Michael Mann, a spokesman for European Union foreign policy chief Catherine Ashton, said the meeting will examine "how existing gaps in positions could be narrowed."
Earlier rounds of negotiations this year in Istanbul, Baghdad, and Moscow made little progress.
Western states and their allies accuse Iran of moving to develop weapons-grade material.
Iran says it only seeks nuclear development for electricity and medical applications.
Based on reporting by DPA, AP, and nytimes.com