U.S. says it awaits Iran's 'credible steps' on nuclear issue WASHINGTON (Reuters) - The inauguration of Iranian President Hassan Rouhani is a chance for that country to move quickly to resolve concerns about its nuclear program, but the United States wants to see actions from Tehran, the State Department said on Tuesday. The inauguration of Rouhani, who took his oath on Sunday, "presents an opportunity for Iran to act quickly to resolve the international community's deep concerns over their nuclear program," said State Department spokeswoman Jen Psaki. She added, however, "there are steps they need to take to meet their international obligations and find a peaceful solution to this issue, and the ball is in their court." Rouhani, seen in the West as a relatively moderate leader, told his first news conference on Tuesday he was "seriously determined" to resolve the dispute and was ready to enter "serious and substantive" negotiations. Asked about those remarks, Psaki said, "we want to see credible steps taken" to address concerns that a nuclear program that Tehran says is purely for peaceful needs is actually an effort to build a nuclear bomb. Reporting by Paul Eckert; Editing by Eric Beech