Onus on Iran to show seriousness on nuke program: US

The United States today said that the onus is on Iran to demonstrate that it is serious in complying with its international obligations in particular those related to its controversial nuclear weapons program.

"The onus is on Iran to demonstrate that it is serious about complying with its international obligations," White House Press Secretary Jay Carney told reporters at his daily news conference, a day after President Barack Obama directed Secretary of State John Kerry to hold talks with the Iranian Foreign Minister on Tehran's nuclear weapons program.

Carney said Obama is "not disappointed" over the reluctance of the Iranian President, Hassan Rowhani, for a chance encounter with him on the sidelines of the UN General Assembly session in New York.

"US President is not (disappointed). He was open to the possibility of an informal encounter with President Rowhani and remains open to that, as he has, broadly speaking, since he took office," Carney said in response to a question.

"The President believes that the most important issues, when it comes to Iran's relationship with the rest of the international community, including the United States, are ones that need to be resolved through negotiations over substantive matters around Iran's nuclear weapons programme," he said in response to a question.

Asserting that the windows of diplomatic options is still open with Iran, Carney said this is not going to remain open indefinitely.

Tough international sanctions, led by the US has resulted in Iran's willingness to come forward towards diplomatic negotiations.

"I think President Rowhani made clear and others have made clear, has had a dramatic impact on the Iranian economy and that is why Iran is interested in, in our view, having discussions about resolving this conflict. And that is encouraging," he said.

"But actions are what matter, and substantive negotiations over Iran's nuclear programme will be the test, will provide the test of whether or not Iran is serious about resolving the international community's concerns," he said.

United States, he said has been and continues to this week explore the level of seriousness by Iran on its nuclear weapons programme.

"We are doing that through all the avenues available to us. That will be very much part of the discussions that Secretary Kerry has, and it is part of the communications that we have had, including the communications that the president had in his exchange of letters," he said.

"So the Iranians have to decide, most importantly through substantive negotiations, whether or not they want to truly resolve this. And through resolution of it, through a verifiable, confirmable agreement to give up its nuclear weapons ambitions, Iran can then rejoin the international community, end its isolation, enjoy relief from the sanctions regime," he asserted.