President Barack Obama said Friday that he and Iran's Hassan Rouhani conducted a telephone conversation about Tehran's nuclear program, the first direct contact between the U.S. and Iranian heads of state in more than 30 years.

"Just now, I spoke on the phone with President Rouhani of the Islamic Republic of Iran," Obama told reporters at the White House.

"The two of us discussed our ongoing efforts to reach an agreement over Iran's nuclear program. I reiterated to President Rouhani what I said in New York - while there will surely be important obstacles to moving forward, and success is by no means guaranteed, I believe we can reach a comprehensive solution," Obama said.

He said Secretary of State John Kerry will pursue the diplomatic initiative with the Iranian government.

"Going forward, President Rouhani and I have directed our teams to continue working expeditiously ... to pursue an agreement," Obama said.

The process will include Britain, France, Germany, Russia, China and the European Union, he said, adding that Washington will also remain "in close touch with our friends and allies in the region, including Israel."

Iran says its nuclear program is oriented exclusively toward power generation and the production of isotopes used in medicine. But Israel and some Western countries suspect Tehran is seeking nuclear weapons capability.

Iran will not develop nuclear weapons, Rouhani vowed this week in a speech to the U.N. General Assembly. EFE