Obama and Iran's Rouhani speak

President Barack Obama spoke by telephone with Iranian President Hassan Rouhani on Friday, in the first conversation between U.S. and Iranian presidents in more than 30 years.

“Just now, I spoke on the phone with President Rouhani of the Islamic Republic of Iran,” Obama said in a televised address on U.S. international policy and the looming government shutdown.

A senior administration official said in a phone conference that the call took place at 2:30 p.m. EDT and lasted 15 minutes. Obama congratulated Rouhani on his recent election and said Rouhani's statements, including his recent speech at the U.N. General Assembly, had been "constructive."

Obama also addressed concern over the continued detention of three U.S. nationals: Amir Hekmati, Saeed Abedini and Robert Levinson.

He said goodbye to Rouhani in Farsi — "khodahafez" — after the two communicated through an interpreter. 

Obama said in his televised address that after their conversation, he believes the United States and Iran can reach a comprehensive solution to the international impasse over Iran's nuclear program.

The U.S. leader said he and Rouhani have directed their respective teams to work quickly to pursue an agreement. He said Washington will coordinate closely with its allies — including Israel, which considers Iranian nuclear weapons capability an existential threat.

Senior administration officials said Washington was in touch with the Israeli government before the call. 

Iranian and U.N. officials have been meeting to continue talks on how to investigate suspicions that Iran has secretly worked on developing nuclear weapons. Tehran denies that claim.

Rumors circulated that Rouhani and Obama would meet in person at a lunch for world leaders hosted by U.N. Secretary-General Ban Ki-moon on Tuesday after the two spoke at the General Assembly. But Rouhani did not attend, because alcohol — prohibited by Islam — was served at the meal, Iranian state media reported.

Al Jazeera's Massoud Hayoun contributed to this report. With wire services