U.S. Secretary of State Hillary Rodham Clinton says the United States is working "expeditiously and thoroughly" to win new international penalties on Iran over its disputed nuclear program.

Clinton told reporters traveling with her in South America that a new sanctions resolution is likely to come before the United Nations Security Council sometime in the next several months.

That's far later than the United States once hoped for, in part because of reluctance among some other members of the Security Council.

Clinton is recruiting support for the Iran penalties. She says she will make sure that the president of Brazil, which has close ties to Iran, knows the extent of world alarm over Iran's activities.