"Confusion is a good word," deputy State Department spokesman Adam Ereli said of the mixed messages emanating from Tehran. "They're saying different things, we're saying the same thing."
"We hope that Iran will see this resolution as an opportunity to respond to straightforward questions in a clear, concise manner, and to take the other steps needed to comply with the (IAEA) resolution," he told reporters.
"Actions speak louder than words," Ereli said. "Let's see them take the actions that are called for."
Last week, the IAEA's governing board gave Iran an October 31 deadline to address concerns about its nuclear program prompting angry responses from Tehran, whose delegation walked out of the meeting in protest.
By that date, the IAEA called for Iran disprove US allegations that it is secretly developing nuclear weapons.
If it does not, US officials have suggested that the IAEA refer the matter to the UN Security Council which could impose sanctions on Tehran.
Iran's ambassador to the IAEA, who led the walkout at Friday's meeting, said afterward that Iran was reconsidering its cooperation with the UN watchdog and might even withdraw from the nuclear Non-Proliferation Treaty (NPT).
But his comments were contradicted on Monday when Iranian vice president and atomic energy agency chief Gholamreza Aghazadeh said that Tehran remained fully committed to the NPT despite its objections to the deadline.