"We remain open to engagement. But they do know what they have to do. They have to reassure the international community by words and actions as to what their nuclear program is intended for," she said in an interview with The New York Times.
"And so whether it would take six months, a year, or five years, it's that deep concern about Iran acquiring nuclear weapons that is the preoccupation of our friends and partners," she said.
"And we would be pursuing the path we're pursuing regardless of any issue of timing because we think it's got the best potential for changing Iranian behavior."