Secretary of State Condoleezza Rice said Thursday an international consensus is growing for referring the issue of Iran's nuclear program to the U.N. Security Council. She gave no time-line but said the need for such action is becoming clearer.

The United States, which maintains that Iran is seeking nuclear weapons, has long held out the prospect of a Security Council referral for possible sanctions if European efforts to persuade Iran to give up its nuclear ambitions fail.

In a breakfast talk with State Department reporters, Ms. Rice said a referral is not just an idle threat or saber rattling, and that U.S.-led diplomacy has produced a consensus for such action "at the right time, at the time of our choosing".

"I think that what you're seeing is that people want the Iranians to decide whether or not they're prepared to live with a civil-nuclear structure that does not raise proliferation risks, or not," she said.  "And when it is clear, as it is becoming clear, that they are not prepared to do that, I think you'll have a very strong consensus behind a different course of action."

Ms. Rice said she hoped diplomatic efforts short of action in the Security Council are not exhausted. However, she said that by failing to be responsive to nuclear initiatives by the EU-3 - Britain, France and Germany - and an alternate effort by Moscow, the Tehran government is increasing its own isolation.

She said that process has been accelerated by threats against Israel and other recent statements by Iranian President Mahmoud Ahmadinejad, who she said has seemed intent on reminding people why Iran never could be trusted with nuclear technology.

Ms. Rice drew a distinction between the current leadership in Tehran and the Iranian people, and said she wished there were ways by which the United States could interact with Iranians. "Nobody wants to isolate the Iranian people," she added.  "If there were ways to better engage and reach out to the Iranian people, I would love to see them. You know, soccer matches and musicians and university students and all of those things, because this is a great civilization and these are a great people. They happen to have a leadership that seems at this point to have chosen confrontation rather than cooperation with the international system."

The United States and Iran have not had diplomatic relations since Iran's Islamic revolution in 1979, when student militants invaded the U.S. embassy and held U.S. diplomats hostage for more than a year.

The two countries have had occasional political contacts, but cultural exchanges have been minimal.