In a speech on the last day of the International Monetary Fund annual meetings in Tokyo, Federal Reserve Chairman Ben Bernanke defended his organization against critics who say its policies are destabilizing currencies abroad.

Critics argue that the Fed's decision last month to inject $40 billion into the U.S. economy is driving investors away, destabilizing currencies. While Bernanke said he was "sympathetic to the challenges faced by many economies" abroad, he argued that the link between the Fed's actions and the emerging-economy problems is overstated, and that policymakers overseas have made matters worse by resisting currency appreciation.

By boosting U.S. spending and growth, Bernanke said, the Fed's recent actions will help "support the global economy as well."