Secretary of Supreme National Security Council of Iran Saeed Jalili is said to meet EU High Representative Catherine Ashton shortly, IRNA reported.
Diplomatic sources in Istanbul say Jalili and Ashton decided to meet one the sidelines of Iran-P5+1 talks.
Jalili-Ashton talks, held while the US envoy kept away, are said to be worth pondering.
Delegates will hold talks after Jalili-Ashton negotiations.