Moscow is concerned that Tehran has not yet formed a delegation to negotiate with the six world powers on Iranian nuclear issue, Russian Deputy Foreign Minister Sergei Ryabkov told RIA Novosti.
"The process of formation of the delegation has not yet been completed, and this worries us. We are also concerned that the date and place of the talks of six world powers have not been agreed. We call on other members of the six world powers and Iran to agree on a place and time of the next round of talks as soon as possible," Ryabkov said.