According to AFP, Kerry and Zarif arrived simultaneously on the first floor of a leading Geneva hotel in opposite elevators and greeted each other with smiles and a handshake.

They chatted as they walked together along the corridor to the meeting room on the same floor.

Asked by a journalist, whether they expected to meet the nuclear negotiating deadline, Zarif smiled and said: "We will try." Kerry did not respond.

Zarif deputies Abbas Araqchi and Majid Takht Ravanchi as well as Kerry’s aid Wendy Sherman and the EU foreign policy deputy Helga Schmid are also participating in the session.

The US secretary of Energy Ernest Moniz is also in Geneva for the same purpose.

Recent developments in nuclear negotiations may signal that the talk for drafting the final nuclear deal is entering a new level, IRNA reports.

Iran's Deputy Foreign Ministers Abbas Araqchi and Majid Takht-e Ravanchi and the EU Political Director Helga Schmid conferred on Iran's nuclear issue on Wednesday.

Consultations between Zarif and Kerry will help narrow differences between Tehran and the P5+1 countries over writing the text of a final agreement.

All these political developments prove the fact that all sides are serious to make the deal and draft the final comprehensive agreement.

Araqchi, Ravanchi and Schmid held three rounds of talks in Vienna as well as other separate talks in New York last month (April-May) in order to draft the text of final comprehensive deal.The two sides have set July 30 as the deadline for a final deal.