White House: Iran's nuclear proposal serious, substantial

A proposal offered by Iranian negotiators in Geneva aimed at addressing its nuclear program shows a level of seriousness and substance that the United States had never seen before, the White House said on Wednesday. White House spokesman Jay Carney said the Iranian proposal was "very useful" although he cautioned that "no one should expect a breakthrough overnight."

"The Iranian proposal was a new proposal with a level of seriousness and substance that we had not seen before. These are complicated issues... and as the president has said, the history of mistrust is very deep," he said. (Reuters)