Iran’s President Hassan Rouhani has said that if he and his foreign minister had not directly talked with the U.S. Secretary of State and President Barack Obama, the 2015 nuclear agreement would not have been possible.

In a speech he delivered in the Iranian foreign ministry on Tuesday Rouhani said that in September 2013 in the last moments of his trip to the UN General Assembly in New York he accepted a phone call from Obama. This was the first contact between an Iranian and a U.S. president since the 1979 revolution.

During the same week, Iran’s Foreign Minister Mohammad Javad Zarif negotiated with the U.S. Secretary of State John Kerry on the sidelines of nuclear talks between Iran and world powers.

Iran’s Supreme Leader Ali Khamenei at the time endorsed the efforts of Rouhani and Zarif but indirectly criticized their direct talks with Obama and Kerry.

Rouhani’s visit to the foreign ministry followed the visit of the parliament speaker a day earlier on August 5, apparently both in show of support for Zarif after he was sanctioned by the United States last month.

In his speech Rouhani tried to dispel any impression of a rift among Iran’s ruling establishment over foreign policy. He reiterated that he might disagree with some decisions made through “constitutional” bodies, but once the decision is final, he has to carry it out.

“This is not a dichotomy” Rouhani said adding, “If a decision is made through the decision-making processes, we are all duty-bound to execute it”.

Nevertheless, Rouhani also reiterated that one of the reasons why his supporters voted for him was his call for “constructive interaction with the world”. He added that confrontation is easy, but interaction is hard. “To throw insults” at the world is easy Rouahni said, praising Zarif for his experience and scholarship.