The U.S. has not offered a guarantee against attacking or undermining Iran's hard-line government in exchange for having Tehran curtail its nuclear program, Secretary of State Condoleezza Rice said Sunday.

"Iran is a troublemaker in the international system, a central banker of terrorism. Security assurances are not on the table," Rice said.

The European Union said last week it would propose economic and political incentives to persuade Iran to halt its plans for enriching uranium. While Iranian officials contend they are only seeking nuclear power, the U.S. and other nations fear Iran is working toward developing weapons.

Rice, appearing on Sunday news shows, said European officials have not asked the U.S. for security guarantees as they discuss options for dealing with Iran. She did not say what the U.S. response would be if asked to provide such an assurance.

"What we're talking about is a package that will make clear to Iran that there are choices to be made," she said on "FOX News Sunday."

"Either that there will be sanctions and actions taken against Iran by the international community or there's a way for them to meet their civil nuclear concerns," she said on FOX, where she also used the "troublemaker" label.

Diplomats have said that Mohamed ElBaradei, who heads the International Atomic Energy Agency, would meet with Rice and President Bush's national security adviser, Stephen Hadley, this week in Washington. In addition, representatives from the five permanent U.N. Security Council members, the EU and Germany plan to met in London to talk about Iran.

Rice said she thought it was strange even to discuss security guarantees when Iran threatens Israel, promotes terrorism in the Middle East and stirs up violence in southern Iraq to the detriment of U.S. forces.

Asked on NBC's "Meet the Press" if Bush would leave office with nuclear arms being developed in Iran, Rice said: "We can't allow Iran to steadily turn toward nuclear weapons because it would be tremendously destabilizing in this already volatile region. We have a lot of tools at our disposal."

Rice dismissed as "high talk" the statement last month by Iran's president, President Mahmoud Ahmadinejad, that his country would not "give a damn" about U.N. resolutions that could penalize Tehran.

"The Iranians know that sanctions, that international action can, in fact, be quite damaging to them," she said. "And so I assume that the Iranian president is simply posturing on this because I think the Iranians do know how devastating this could be."

Israeli Prime Minister Ehud Olmert told a cable news channel that he believes Iran is just a few months rather than a few years from acquiring the technological expertise needed to build a nuclear bomb.