U.S. President Barack Obama says a nuclear agreement with Iran is "possible" and would be a necessary first step in any greater diplomatic engagement between the two countries.
In an interview with National Public Radio (NPR), Obama said he would be hopeful about working to improved relations under a scenario with an Iran that has a verified peaceful nuclear program, whose economy grows unhampered by sanctions and is "reintegrated into the international community."
NPR posted a transcript of the president's interview on its website early Monday.
Obama said Iran has a chance to "break through" isolation and resolve the nuclear issue, and that Iranian officials should seize the opportunity.
When asked if the United States would open an embassy in Tehran, following a move toward closer relations with Cuba this month, the president said he would "never say never." But he cautioned that "these things have to go in steps."
The U.S. severed diplomatic relations with Iran in April 1980, several months after Iranian activists seized the U.S. Embassy in Tehran and took its staff hostage.
More recently, the United States has been working for years along with Britain, China, France, Russia and Germany to ensure that Iran is using its nuclear facilities for peaceful, civilian purposes rather than developing weapons. Iran has long denied its program has military aims, saying it only wants to use nuclear material for things like generating power and medical research.
The two sides agreed to an interim deal in November 2013, but failed to reach a comprehensive deal by their self-imposed deadline last month. They have extended the talks into next year with a new deadline at the end of June.
Last week, Iranian Foreign Minister Javad Zarif expressed confidence the two sides will meet their goal, but cautioned again that the so-called P5+1 group should not make unrealistic demands in curbing Iran's nuclear activity.