Updated

The world must help the United States stop Iran (search) and North Korea (search) from acquiring nuclear weapons if it wants to avoid military action like in Iraq, U.S. national security adviser Condoleezza Rice said Thursday.

"We don't ever want to have to deal with the proliferation issue again the way we dealt with Iraq," Rice told the International Institute for Strategic Studies (search).

"If you don't want a made-in-America solution, then let's find out how to resolve the North Korean case and the Iranian case."

The United States fears Iran and North Korea are using civilian nuclear power programs as cover for building atomic bombs. Last year, President Bush named both countries, along with Saddam Hussein's Iraq, as being part of an "axis of evil."

Bush has called for strong action -- including "active interdiction" of suspicious cargoes -- to stop the spread of nuclear, chemical and biological weapons.

Some fear that, in the wake of the war on Iraq, the U.S. administration plans military attacks on other countries it suspects of possessing such weapons.

Rice did not rule out armed action against North Korea.

"I don't think we can speculate about where an interdiction initiative should lead, but it's extremely important that countries like North Korea recognize that if they are going to flaunt their international obligations, there will be a cost for it," she said.

"The North Koreans have to be stopped and the world has to stop them. How far it will go, I think none of us can predict."

Rice said reports by the International Atomic Energy Agency about Iran's nuclear program were "at the very least disturbing." She said Iran should allow inspectors unfettered access to verify it was not developing nuclear weapons.

Iran has said it will continue to limit the operations of the U.N. nuclear watchdog.

"The United States cannot face up to this alone," Rice said. "This is something the international community must do."

In an address to journalists, politicians and foreign-affairs analysts, Rice said the world had nothing to fear from a "unipolar" world with the United States as sole superpower.

Rice said the United States, European nations and other "freedom-loving countries," united by a "confluence of common interests and common values," should work together to fight terrorism, rebuild Iraq and ease tensions in the Middle East. She is heading to the region later this week for meetings with Israeli and Palestinian leaders.

Some countries have questioned the U.S. administration's commitment to multilateralism.

When the United Nations refused to authorize force to disarm Saddam earlier this year, the United States did so unilaterally, supported by what Bush called a "coalition of the willing." American leaders said more than 30 countries participated, but only Britain and Australia provided substantial military forces.

Rice said the United States was committed to exercising its power with "humility, not hubris."

"We want multilateral solutions, but we want solutions," she said. "Post 9/11, the sense of urgency in the United States to have solutions to these problems has grown."