A senior administration official told reporters that Iran had denied President Obama's request to meet Rouhani "on the sidelines" of the general assembly.
"We did not have any plan for a formal bilateral meeting here," the official said. "We indicated that the two leaders could have had a discussion on the margins if the opportunity presented itself. The Iranians got back to us; it was clear that it was too complicated for them to do that at this time given their own dynamic back home."
The official emphasized that "nobody contemplated a formal bilateral meeting or a negotiation of any sort."
"We’re not prepared for heads of state to negotiate or Presidents to negotiate on the nuclear issue," the official continued, saying that the Iranians have their own "internal dynamic" to manage politically at home.
The entire diplomatic effort was conducted on site in New York over the past two days.