Leaders of the world's 20 biggest economies have pledged to withdraw their stimulus measures carefully following global concern about the U.S. Federal Reserve's plan to wind down its bond-buying program.

Stock and currency markets in emerging economy countries have recently been rattled by the prospect of the Fed scaling back its policy of quantitative easing.

The G-20 leaders, including the U.S., sought to assuage those fears Friday when they pledged in a joint communique to remain "mindful of the risks and unintended negative side effects of extended periods of monetary easing."

"Our central banks have committed that future changes to monetary policy settings will continue to be carefully calibrated and clearly communicated," the statement said.