From VOA News, 22 April 2009, by David Gollust, State Department [my emphasis added - SL]:
Secretary of State Hillary Clinton says the United States is laying groundwork for new sanctions against Iran if outreach to Tehran on its nuclear program fails to produce results. Clinton says the Obama administration's call for dialogue provides more leverage in efforts to persuade Iran to halt uranium enrichment.
Clinton told Congress the administration's conciliatory policy toward Iran is not open-ended, and that if efforts to persuade that country to halt enrichment and return to negotiations on its nuclear program fail, Tehran would face tighter sanctions.
The Secretary raised the prospect of additional sanctions at a House Foreign Affairs Committee hearing under questioning from committee chairman Howard Berman, who said he is concerned Iran might see a more friendly U.S. approach as merely a green light to pursue nuclear weapons...
...Clinton told Berman the Obama administration has no illusions about its engagement with Iran and is operating on two tracks, offering dialogue but also preparing for additional punitive action if the outreach is spurned or inconclusive.
"Yes we are more than willing to reach out to the Iranians to discuss a range of issues assuming they are willing to reach back," said Hillary Clinton. "....But we are also laying the groundwork for the kind of very tough, I think you said, crippling sanctions that might be necessary in the event our offers are either rejected or the process is inconclusive or unsuccessful."
The Secretary said the administration's effort to engage Iran - on the nuclear issue and other topics - will strengthen its position in a drive for additional international sanctions if that proves necessary.
...Efforts by the previous administration for more sanctions were blocked last year amid resistance from Russia and China...
Hear the Gollust report: Download (MP3) or Listen (MP3)
Video: Clinton on a Nuclear Iran: Download (WM) or Watch (WM)