"We have spent time listening and working hard to create this common ground and these common interests, and we've done it out of a sense of mutual respect," she said. "We respect and admire so many other cultures and societies."
"But we do feel like at a certain point, the international community must speak with one voice, and we think that time has come with respect to Iran’s nuclear program," she added.
Clinton did not say, when asked, whether the United States would support an Israeli attack on Iran's nuclear sites, but she did express disappointment at Iran's diplomacy.
"What we have tried to do is engage in diplomacy in a very vigorous way in order to reassure the international community, including all states, that Iran's nuclear program was for peaceful purposes," she said. "Unfortunately, we haven't had the kind of response we were hoping for from the Iranians."
"I think the international community really still wants to engage with Iran, but people are going to now turn to other routes like more pressure, like sanctions to try to change their mind and their behavior," she said.