Iran on Wednesday urged Western powers to be "realistic" in talks to revive a 2015 nuclear deal and said its top negotiator was returning to Tehran for consultations, suggesting a breakthrough in its discussions is not imminent.
After 10 months of talks in Vienna, progress has been made toward the restoration of the pact to curb Tehran's nuclear program in exchange for sanctions relief, but both Tehran and Washington have cautioned that still there are some significant differences to overcome.
