Speaking to the National Foreign Trade Council in New York, Rubin said US leadership was crucial to help the world overcome its worst crisis in half a century.

"After almost six years in government, I have become deeply concerned that public support for forward-looking international economic policies may be waning at a time when our country's economic, national security and geopolitical interests require just the opposite," he said in prepared remarks.

A copy of his speech was released in Washington. Rubin reiterated previous warnings that it would take much time and effort to restore stability and growth in the battered world economy. But he also noted there had been "a number of significant positive developments over the last few months."

He mentioned efforts to clean up Japan'sdebt-ridden banks, recent US Congressional approval to beef up the resources of the International Monetary Fund, and a shift in policy among developed nations away from worrying about inflation toward concern over weakening growth as steps in the right direction.

But he said he was worried about "increased expressions of concern about the openness of our markets, despite our healthy economy, remarkably low unemployment, and rising wages."

Rubin noted market-based economic systems offered the best path to economic well-being around the world, but cautioned that the international mechanisms designed to prevent crises or deal with them when they occur needed to be beefed up.

At the same time, more work needed to be done to distribute the benefits of the global economy more evenly across society while at the same time increasing the understanding of the need for American leadership in the world, he added.

"Unless there is broad public understanding of these matters, we risk moving backward, withpotentially serious economic and national security consequences," he said.